kck@g.gp.cs.cmu.edu (Karl Kluge) (02/17/89)
> From: harnad@elbereth.rutgers.edu (Stevan Harnad) > > Tell me, down there in the trenches, can you still tell the difference > between this: (1) "Koran reggel ritkan rikkant a rigo" and this: (2) > "How much wood could a woodchuck chuck if a woodchuck could chuck > wood"? Call that difference "X." X is all that's at issue in the > Chinese Room Argument. No word games. Ah, but it is a word game. Here is Searle's Chinese Room argument as I see it. We have Mind A, which we will call John Searle, which understands English, and which in its capacity as a Universal Turing Machine is emulating Mind B, which we will call Fu Bar. Mind A, John Searle, does not understand what is going on in Mind B, Fu Bar, whose execution it is simulating. So what? How does this in any way, shape, or form establish that Mind B does not understand Chinese in exactly the way that Mind A understands English? Suppose that Searle underwent some traumatic experience that led to his suffering from multiple personality disorder in such a way that personality 1 was the usual old John Searle, while personality 2 did nothing but execute the rules for manipulating Chinese characters (to the point of not responding to English). What possible conclusion could any rational individual encountering this unfortunate make other than that his body contained two minds, one speaking and understanding English, and the other reading and writing in Chinese. How, without the benefit of introspection that we are positing is missing, could Searle deny that this other mind running on his brain really "understood" Chinese? I'm very serious about this, I really don't understand the point Searle believes he is making (or at least, I don't buy that he proves the point - I don't buy the analogy with simulating a forest fire). Karl Kluge (kck@g.cs.cmu.edu) --
rapaport@sunybcs.uucp (William J. Rapaport) (02/18/89)
In article <4298@pt.cs.cmu.edu> kck@g.gp.cs.cmu.edu (Karl Kluge) writes: > >Suppose that Searle underwent some traumatic experience that led to his >suffering from multiple personality disorder ... Just such a situation has been discussed in: Cole, David (1984), "Thought and Thought Experiments," _Philosophical Studies_ 45: 431-444. and replied to by me in: Rapaport, William J. (1986), "Searle's Experiments with Thought," _Philosophy of Science_ 53: 271-279. See also my recent: Rapaport, William J. (1988), "To Think or Not to Think" _Nous_ 22: 585-609. William J. Rapaport Associate Professor Dept. of Computer Science||internet: rapaport@cs.buffalo.edu SUNY Buffalo ||bitnet: rapaport@sunybcs.bitnet Buffalo, NY 14260 ||uucp: {decvax,watmath,rutgers}!sunybcs!rapaport (716) 636-3193, 3180 ||fax: (716) 636-3464
staff_bob@gsbacd.uchicago.edu (02/18/89)
>Ah, but it is a word game. Here is Searle's Chinese Room argument as I see >it. We have Mind A, which we will call John Searle, which understands >English, and which in its capacity as a Universal Turing Machine is >emulating Mind B, which we will call Fu Bar. Mind A, John Searle, does not >understand what is going on in Mind B, Fu Bar, whose execution it is >simulating. > >So what? How does this in any way, shape, or form establish that Mind B does >not understand Chinese in exactly the way that Mind A understands English? > [deleted] >Karl Kluge (kck@g.cs.cmu.edu) I seem to have gotten lost in this discussion. Perhaps someone can help me out of this. Without ever having read the now infamous 'Chinese Room Argument', my understading of it is as follows: Given any natural language, in this case Chinese, it is possible for someone with the proper tools (e.g. a dictionary, a grammar book and lots and lots of time) to communicate in that language without really 'understanding' the language. The theory is that such translation, which involves nothing but the manipulation of symbols, requires no actual understanding of the language. Since this is what computers do, computers do not 'understand' the language they are translating. Is this at least the jist of the argument? Suppose that it is. Those of you who have said that yes, the translator 'understands' what he is translating, seem to be stretching my commonplace definition of understanding more than just a little. This does not vindicate Searle, but I think proceding along these lines is rhetorical sophistry. Arguing about what constitutes 'understanding' does not make Searle's point disappear. In particular, consider the recent argument that if a Chinese speaking person thinks I understand Chinese, then I must in fact understand it, regardless of what *I* believe I understand. To me, this seems consistent with the prevalent 'native speaker' definition of language, and so plausible on the surface. On deeper consideration, however, one sees that the argument is being used to subvert itself. Searle thinks he knows what 'understand' means, and as a native speaker of his own language, I suppose he has that right. One cannot seriously use the 'native' understanding of a Chinaman to invalidate my own understanding of English. If you buy into this definition of lingusitic validitiy, then you shouldn't quibble with definitions at all. If, as a native speaker, I say I don't 'understand', then I don't. Period. Yes, Searle does 'play fast and loose' with his definitions. Unfortunately, the 'native speaker' argument allows him to do exactly that. The point I'm trying to make here is that argument along these lines is generally not productive. Disputing defintions, and derivations based on those defintions, has unfortunately become a part of our (Western) intellectual heritage. When Minsky says that words should be our servants, and not our masters, is he not recognizing this very fact? A definition is generally not a theorem, and it is a mistake to reason from a definition as if it were a theorem. Anyone who takes a moment to reflect should realize the Searle is making a valid point - there is a difference between what I (and Searle) call understanding and what this supposed translator is doing in his Chinese Room. If Minsky, or anyone else, has a different definition of understanding, so be it. That in itself does not invalidate the point which Searle is trying to make. The problem with Searle's argument, as I see it, is equally obvious. Anyone who has ever studied a language, or who has tried to write a program to do so knows that one need substantially more than a dictionary and a grammar to do the job. Serious thinkers no longer believe that simple symbol manipulation is up to the task. In part, this is because of the context sensitivity of language. In general, it is a result of the fact that a (natural) language is not a self contained mathematical system. Understanding language requires a context of understanding which is larger than the atoms and rules which can be said to constitute a particular language. In part, Searle's human translator possesses this context. But this fact works against Searle, not for him. If the human, qua human, cannot be said to 'understand', then certainly the machine cannot. That much is clear. However, this sidesteps the fact that even with the sort of domain knowledge which all humans have, and which seems requisite to true understanding, I don't believe that a human being could actually accomplish the task assigned him in his Chinese Room. If one somehow limits the language domain so that a human could, I suspect that a machine could also. Fooling a native language speaker is not an easy task, a fact that can be attested to by any one of millions of immigrants living in this country. (For an excellent proof of this, see yesterday's posting to REC.HUMOR.FUNNY entitled 'Signs Of Our Times', which contains any number of hilariously funny 'translations', many of which seem to have been made by people with some knowledge of English and a dictionary. One of my personal philosophical interests is why people find such mistakes so very humorous.) My point then, is this: to successfully translate a language, a human being needs not only a grammar and a vocabulary and the domain knowledge which is his by virtue of being human. He needs something else - at least of modicum of 'understanding' of the particular language he is translating. The problem with machine translation is not primarily one of syntactic transformation and word substitution. If it were, we would have mastered machine translation 10 years ago, and Searle's argument against machine understanding would be valid. The problem with machine translation today is that we must impart to the machine not only a knowledge of the nuances of the language being translated, but we must also give it much of the domain knowledge which we, as humans, take very much for granted. If (and this is not a very small if) we ever manage to accomplish this, and thereby establish a proper context for machine translation, then as I see it, Searle is unable to argue that we have not also established a context for machine understanding. I suppose that it is technically true that everything done on a computer can be reduced to the level of abstract symbol processing. To point to this low level of computer processing and then to talk about the very high level capabilities of the human brain and ask 'How can one be the other?' is rhetoric of the very worst kind. To begin with, it ignores the fact that we can reduce the operations of the brain to a very low level and then show, mathematically, that the computational capabilities of neurons and computers are in fact equivalent. What Searle points to as evidence of man's difference from machines are direct consequences of the incredibly complex organization of these low level neurons, which has been achieved only after billions of years of evolution. There is as yet no theorectical reason why we cannot eventually learn to create similarly complex machines. If we understood how neurons can be organized in such a way as to produce cognitive functions such as 'understanding' or 'creativity', then we could say exactly how 'one can be the other'. Until then, arguments such as these are most likely going to be quite common .
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/19/89)
kck@g.gp.cs.cmu.edu (Karl Kluge) of Carnegie-Mellon University, CS/RI wrote: " Ah, but it is a word game... We have Mind A, which we will call John " Searle, which understands English, and which in its capacity as a " Universal Turing Machine is emulating Mind B, which we will call Fu " Bar. Mind A, John Searle, does not understand what is going on in Mind " B, Fu Bar, whose execution it is simulating. Ah me. Is it really so difficult to see that in the above you have simply presupposed the conclusion you were trying to demonstrate? Before we buy into any dogmas, it is a fact that Searle has a mind, but definitely NOT a fact that "Fu Bar" has a mind. OF COURSE if we could simply presuppose that Fu Bar had a mind, or "define" it as having a mind, everything would come out just as you would like. But that's not just a word game: It's circular. " Suppose that Searle underwent some traumatic experience that led to his " suffering from multiple personality disorder... Irrelevant again. That Searle has a mind (at least one) is not in doubt. That the symbol-manipulator does is. That Searle might have had more minds, one English and the other Chinese, is perhaps possible, but he probably doesn't; and even if he did, it's irrelevant. -- Or do you really believe that simply going through the motions of what he does in the Chinese room would be "traumatic" enough to induce multiple personality disorder (plus glossolalia in Chinese)? Yet even THAT would be irrelevant, because you have not shown that his computer counterpart had a mind in the first place, to be similarly traumatized. All of this is certainly word games and sci-fi fantasy, to which any argument, correct or incorrect, deep or shallow, simple or complex, can be reduced. Searle's argument is simple but deep. Its simplicity has led a lot of people who have not understood the deeper point it is making into irrelevancies of their own creation. To show it to be incorrect you must first understand it. " I'm very serious about this, I really don't understand the point Searle " believes he is making... You can say that again... -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
steyn@eniac.seas.upenn.edu (Gavin Steyn) (02/20/89)
In article <Feb.18.17.26.17.1989.23438@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >Before we buy into any dogmas, it is a fact that Searle has a mind, but >definitely NOT a fact that "Fu Bar" has a mind. > >Irrelevant again. That Searle has a mind (at least one) is not in >doubt. I'm sorry, I don't believe Searle has a mind. In fact, everyone is just a symbol processing box (the equivalent of Fu Bar). So, I doubt Searle has understanding. Now, can you prove me wrong? Or, since you probably don't know Searle that well, prove to me that you have a mind, and aren't a symbol manipulator. I don't believe it's possible for you to do so, in which case Searle's argument degenerates into proving that none of us are actually intelligent. Gavin Steyn
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/20/89)
steyn@eniac.seas.upenn.edu (Gavin Steyn) of University of Pennsylvania
writes:
" [1] I don't believe Searle has a mind... [2] everyone is
" just a symbol processing box... can you prove me wrong?
You're certainly entitled to say (1). That's just an instance of the
familiar "other minds" problem: There's no way to know for sure
that anyone else but oneself has a mind. On the other hand, [2] is
just an obiter dictum, hand-waving, a bald claim (one that also happens
to be believed by a lot of current AI investigators simply because
they have not thought very deeply about any of this).
I certainly can't "prove" you wrong about [1]. No one can (not even
Searle, though he can of course chuckle privately over the fact that he
knows perfectly well the "unprovable" truth that you are in fact wrong
about him...). And even if you ask for less than mathematical "proof,"
i.e., only ordinary empirical evidence, no one can give you a shred of
it -- and that's the other-minds problem too: All empirical "evidence"
that Searle has a mind (e.g., he has a brain like yours, he looks like
you, he talks like you, he acts like you -- EVEN that he has a symbol
cruncher inside that's running the same program!) is JUST as compatible
with the fact that he HAS a mind as with the fact that he has NO mind
but merely looks, acts etc. just as if he didl So what? That's all just
a restatement of the other-minds problem.
The ONLY one who can know for sure that Searle has a mind is Searle himself.
And the same is true of your mind: YOU know it (don't you? don't you?).
But do you also "know" that you're a symbol-processor? Or that your having
a mind is purely a consequence of your being a symbol-processor? If so,
please share...
No, [2] is a different kettle of fish. It's just a not very deeply
examined notion that is currently in fashion and that Searle's argument
(for those who have been prepared to think deeply enough about it to
understand it) has gone some way toward showing to be incorrect. A more
tenable version of [2] might be:
[2'] everyone EXCEPT ME is just a symbol processing box
but that version just wears its incompleteness and arbitrariness on its
sleeve (which is why no one ever remembers to put it that way).
Some readers know that in my writing I have advocated what I call the
Total Turing Test (TTT) as a methodological constraint in cognitive
modeling. I have also advocated methodological epiphenomenalism.
However, I have never mistaken the TTT for a "proof" or even
empirical evidence. It isn't. Nor have I had to resort to denying the
obvious: That people have minds, just as I do. I have, however, taken
up Searle's torch to show why a "symbol processing box" could not pass
the TTT. It would be useful if those with a serious interest in these
matters would slow down long enough to grasp the logic and the facts
before hurtling on to their respective weighty conclusions...
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771engelson@cs.yale.edu (Sean Engelson) (02/20/89)
I have a simple question for those denying (Searle + rules)
understanding of Chinese: What is your definition of "understanding"
that allows Searle understanding of English, but does not allow
(Searle + rules) understanding of Chinese? It seems that to
demonstrate or refute the position of understanding being demonstrable
purely through I/O behavior, one must have an effective definition of
understanding. By effective I mean one that does not beg the
question, i.e. by defining understanding to be symbol-processing, or
conversely, to be that which humans do.
Any takers?
----------------------------------------------------------------------
Sean Philip Engelson, Gradual Student Who is he that desires life,
Yale Department of Computer Science Wishing many happy days?
Box 2158 Yale Station Curb your tongue from evil,
New Haven, CT 06520 And your lips from speaking
(203) 432-1239 falsehood.
----------------------------------------------------------------------
I know not with what weapons World War III will be fought, but World
War IV will be fought with sticks and stones.
-- Albert Einsteinharnad@elbereth.rutgers.edu (Stevan Harnad) (02/20/89)
engelson@cs.yale.edu (Sean Engelson) of Computer Science, Yale University, New Haven, CT 06520-2158 asks: " for those denying (Searle + rules) understanding of Chinese: What is " your ["effective"] definition of "understanding"... one that does not " beg the question... by defining understanding to be " symbol-processing or... that which humans do. Is anyone reading or understanding these postings? Or thinking about what this is all about? As I've indicated repeatedly, this is NOT a definitional issue! All I have to do is POINT to positive and negative instances! Before you went to graduate school in computer science at Yale, if I had said to you, "Look, you understand English, you don't understand Chinese, correct?" You would have said, "Sure," and you would have been right. Nobody would have had to define understanding, "effectively" or otherwise; and no questions would have been begged. In fact, nobody COULD have defined understanding, then or now, because we still don't know what it is, functionally speaking; finding out what it is and how it works is going to be cognitive science's empirical mission for some time to come. But we can certainly still POINT to understanding , when it's there; and say it isn't there, when it isn't. Now you're in graduate school at Yale, and you aren't so sure about that. Are you sure you're wiser than before? (Please don't reply with a string of cases where degree of understanding is ambiguous; they've already been brought up repeatedly in this discussion before, and I've replied. In a word, they're irrelevant. And don't reply with analogies to other disciplines in which graduate school was right to make you doubt your prescientific intuitions. There has been no science here yet, just promises and hand-waving.) Understanding is what is "+" of Searle (and you) with respect to English, and "-" with respect to Searle (and you, and the computer running the program he's executing) with respect to Chinese. Lacking any other evidence for "+" on the computer's behalf, that makes the score on understanding: Searle 1, computer 0. [This is the negative note on which Searle's Argument ended in 1980; not to leave it at that, let me add that in "Minds, Machines and Searle" (1989) I've tried to take it further in a positive direction, showing that it's only the symbolic approach to modeling the mind that's vulnerable to Searle's Argument; nonsymbolic and hybrid symbolic/nonsymbolic models are not. And in "Categorical Perception" (1987) I have sketched how symbolic representations could be grounded bottom-up in nonsymbolic (analog and categorical) representations. Now, being immune to Searle's argument doesn't guarantee that a model has captured understanding, of course (nor does it "effectively define" understanding). But it does perhaps correct the misapprehension that the validity of Searle's argument (and it IS valid) would entail that NO model could understand; perhaps this misapprehension is behind the strained, implausible and incoherent counterarguments people have tried to float under the general banner of the "Systems Reply." You don't have to give up on "systems". Just give up on purely symbolic systems.] -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
sher@sunybcs.uucp (David Sher) (02/20/89)
Now that we've posted megawords on "understanding" and whether a machine
can or can not posses it, can I ask: what is the advantage of a
machine with "understanding"? Assume that HAL doesn't understand
anything. He merely manipulates symbols so that he creates an illusion
of understanding in his correspondents. In what way does that inhibit
HAL as a useful tool. What could an "understanding" machine that a
merely intelligent (the symbol manipulator that merely gets the right answer)
machine could not? Unless someone can show me an advantage to it I'm not
going to waste much time designing it into my programs.
-David Sher
ARPA: sher@cs.buffalo.edu BITNET: sher@sunybcs
UUCP: {rutgers,ames,boulder,decvax}!sunybcs!sherbwk@mbunix.mitre.org (Barry W. Kort) (02/20/89)
The problem I have with Searle's notion of symbol manipulation is that such a system appears unable to learn anything new. In _Surely You're Joking, Mr. Feynman_, Richard Feynman recounts an attempt to teach physics in Brazil. The students had become very adept at formal symbol manipulation. They could regurgitate the definitions and formulas, but they had no idea that the symbols actually referred to anything in the outside world! It seems to me that "understanding" (or "comprehension", as I prefer to call it) entails the construction of a mental map between symbols and their referents in the world external to our minds. Once we buy into this notion of "understanding", we automatically buy into the notion of "learning" (knowledge acquisition). Searle's Chinese Room could be considered to understand Chinese if it could use the medium of Chinese to acquire knowledge about the world outside the room. Such a system would evolve its "rules" over time. Instead of just translating stories, it would respond with its own anecdotal accounts, maintaining a thematic thread suggested by the preceding stories. --Barry Kort
fransvo@htsa.uucp (Frans van Otten) (02/20/89)
In article <Feb.19.14.23.34.1989.8773@elbereth.rutgers.edu>, harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > >The ONLY one who can know for sure that Searle has a mind is Searle himself. >And the same is true of your mind: YOU know it (don't you? don't you?). You say you're *sure* that you have a mind, you *know* it. How can you be *sure* if you only *know* it ? I say you only had a compile-time flag: program Stevan_Harnad(input, output); const I_HAVE_A_MIND = true; /* The main point */ var alive : boolean; symbol : SymbolType; result : ResultType; begin alive = TRUE; while alive do symbol = Read_Symbol; result = Crunch_Symbol(symbol); if result = dead then alive = false else Output_Result(result); end; end. I want you to show me how you can prove to yourself that you have a mind. Until then I must assume that you are (only) a symbol cruncher, and so must you. -- Frans van Otten Algemene Hogeschool Amsterdam Technische en Maritieme Faculteit fransvo@htsa.uucp
engelson@cs.yale.edu (Sean Engelson) (02/20/89)
In article <Feb.19.18.25.26.1989.15723@elbereth.rutgers.edu>, harnad@elbereth (Stevan Harnad) writes: > > >engelson@cs.yale.edu (Sean Engelson) of Computer Science, >Yale University, New Haven, CT 06520-2158 asks: > >" for those denying (Searle + rules) understanding of Chinese: What is >" your ["effective"] definition of "understanding"... one that does not >" beg the question... by defining understanding to be >" symbol-processing or... that which humans do. > >Is anyone reading or understanding these postings? Or thinking about >what this is all about? As I've indicated repeatedly, this is NOT a >definitional issue! All I have to do is POINT to positive and negative >instances! What is your criterion for determining which is which? I'm not denying that you have one, I'd just like to have it out in the open and explicit. >Before you went to graduate school in computer science at >Yale, if I had said to you, "Look, you understand English, you don't >understand Chinese, correct?" You would have said, "Sure," and you >would have been right. Nobody would have had to define understanding, >"effectively" or otherwise; and no questions would have been begged. >In fact, nobody COULD have defined understanding, then or now, because >we still don't know what it is, functionally speaking; finding out what >it is and how it works is going to be cognitive science's empirical >mission for some time to come. And I can equally well POINT to Searle running his rules for Chinese, and say to (him + rules) in Chinese, "Look, you understand Chinese, don't you?" and I'd expect to get back the answer (in Chinese) "Yes". So why deny the system of (Searle + rules) understanding of Chinese? After all, I can just POINT to it, can't I? >But we can certainly still POINT to understanding , when it's there; >and say it isn't there, when it isn't. Now you're in graduate school at >Yale, and you aren't so sure about that. Are you sure you're wiser >than before? Well, for all external intents and purposes, (Searle + rules) understands Chinese. As I think you are saying, since "plain" Searle does not understand Chinese, (Searle + rules) does not. Why not? What's the difference? >Understanding is what is "+" of Searle (and you) with respect to >English, and "-" with respect to Searle (and you, and the computer >running the program he's executing) with respect to Chinese. Lacking >any other evidence for "+" on the computer's behalf, that makes the score >on understanding: Searle 1, computer 0. In other words, you are DEFINING understanding to be that which Searle has with respect to English, and not that which (Searle + rules) has with respect to Chinese. OK, given that distinction, tell me either how I can distinguish between the two in a Turing-test fashion, or what it is about Searle that allows him to understand English which (Searle + rules) does not have. Otherwise, as I've said, I'll grant you your point, and then say that this whole discussion is pointless, as you're concept of understanding is "That which people do", which is useless. ---------------------------------------------------------------------- Sean Philip Engelson, Gradual Student Who is he that desires life, Yale Department of Computer Science Wishing many happy days? Box 2158 Yale Station Curb your tongue from evil, New Haven, CT 06520 And your lips from speaking (203) 432-1239 falsehood. ---------------------------------------------------------------------- I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones. -- Albert Einstein
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (02/20/89)
From article <Feb.19.18.25.26.1989.15723@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): " ... Is anyone reading or understanding these postings? ... Someone is reading these postings. Someone is not understanding your postings. You know that the other-minds issue is unresolvable, yet you suppose that you have resolved it when you premis your remarks on Searle (and others) having a mind. Someone is confused. Greg, lee@uhccux.uhcc.hawaii.edu
rjc@aipna.ed.ac.uk (Richard Caley) (02/21/89)
In article <Feb.19.18.25.26.1989.15723@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >But we can certainly still POINT to understanding , when it's there; >and say it isn't there, when it isn't. I certainly can't, and it seems to be an assumption of the chinese room that I can't. My understanding is that the bahviour of the searle+room+rules system is to be indistiguiahsble from a native chinese speaker and it is only by opening the room and seeing searle and asking _him_ if he understands that we are supposed to determine that the system does not "understand" chinese. If I _can_ tell understanding systems from non-understanding ones then the whole argument is pointless, since I can never be "fooled" by the room. Understanding is a subjective phenomenon; _I_ know if I understand chinese ( no ) but you only have my word for it. So it _is_ a definitional problem. Since we have assumed that the behaviour is identical whether or not it understands, we must rely on deduction based on the structure of the system to tell us if it understands. Most significantly, we can't rely on the method we use for humans - if we ask the room ( presumably in chinese ), it says yes, otherwise the behaviour is not like that of a native speaker! Without defining understanding we can't argue with it since our intuative knowledge of understanding is only for _ourselves_, we apply it to other people since they seem rater similar, we can _try_ and apply it to philosophers in rooms or computer systems but I would not trust the result - " Hm, it does not have a chinese passport and so ... " >Understanding is what is "+" of Searle (and you) with respect to >English, and "-" with respect to Searle (and you, and the computer >running the program he's executing) with respect to Chinese. Aren't you assuming the result here. If searle running the program is "-" WRT "understanding" the naturally the system does not understand. This is tautological! >Lacking >any other evidence for "+" on the computer's behalf, that makes the score >on understanding: Searle 1, computer 0. If you are trying to prove non-understanding by a default assumption then I would say you prove nothing, since I can just as easily assert that by default we must assume that the system _does_ understand. This is certainly the default I apply to people ( "if they seem to understand chinese then they do - ask them what the menu means" ). Why should it be different for other types of system? >[This is the negative note on which Searle's Argument ended in 1980; >not to leave it at that, let me add that in "Minds, Machines and >Searle" (1989) I've tried to take it further in a positive direction, >showing that it's only the symbolic approach to modeling the mind >that's vulnerable to Searle's Argument; If the argument could be truncated to a reasonable length, then I would be interested if you posed it. I don't see why, say, searle in a room pulling strings and waving springs ( or doing something else equally non-symbolic ) which happens to produce behaviour like a chinese speaker would not be the basis for a precicely parallel argument. I'm not saying you are wrong, just that it is not obvious. -- rjc@uk.ac.ed.aipna " Only love denies the second law of thermodynamics " - Jerry Cornelius
vangelde@cisunx.UUCP (Timothy J Van) (02/21/89)
In article <Feb.19.14.23.34.1989.8773@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > >" [1] I don't believe Searle has a mind... [2] everyone is >" just a symbol processing box... can you prove me wrong? > >that anyone else but oneself has a mind. On the other hand, [2] is >just an obiter dictum, hand-waving, a bald claim (one that also happens >to be believed by a lot of current AI investigators simply because >they have not thought very deeply about any of this). > >No, [2] is a different kettle of fish. It's just a not very deeply >examined notion that is currently in fashion and that Searle's argument >(for those who have been prepared to think deeply enough about it to >understand it) has gone some way toward showing to be incorrect. A more I tend to be sympathetic to just about every point Stevan Harnad has made in this interesting "continental bull session" - except this one. I take it that [2] is just the Physical Symbol System Hypothesis (Newell and Simon), otherwise known as the GOFAI hypothesis (Haugeland). Is this really just a bold claim that nobody would take seriously if they had thought deeply about the issue? Is Harnad saying that Newell and Simon, Pylsyhyn, Haugeland, Fodor etc have not thought deeply about the issue? If so, Harnad has quite remarkably high standards for thinking deeply about the issue - not even some of the most respected minds in cognitive science make the grade. If, by contrast, Harnad really has thought deeply about the issue, he surely belongs in the ranks of Turing, von Neumann, Wittgenstein etc. Now, I happen to think that the PSSH is in fact false. But I also think that it is a very deep and well worked out view - rather better worked out, in fact, than just about any psychological paradigm I can think of. In fact, that's one reason we are now in a position to see its flaws. So I dont want to endorse the position; rather, I just question the rather outrageous claim that anyone who does endorse it cant have thought deeply about the issue. Steve, please reassure me that I have misunderstood you somewhere here... Tim van Gelder
marty1@houdi.ATT.COM (M.B.BRILLIANT) (02/21/89)
From article <Feb.19.18.25.26.1989.15723@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): > > engelson@cs.yale.edu (Sean Engelson) of Computer Science, > Yale University, New Haven, CT 06520-2158 asks: > > " for those denying (Searle + rules) understanding of Chinese: What is > " your ["effective"] definition of "understanding"... one that does not > " beg the question... by defining understanding to be > " symbol-processing or... that which humans do. > ..... > Understanding is what is "+" of Searle (and you) with respect to > English, and "-" with respect to Searle (and you, and the computer > running the program he's executing) with respect to Chinese. Lacking > any other evidence for "+" on the computer's behalf, that makes the score > on understanding: Searle 1, computer 0. As an educated native speaker of (American) English, I know enough about English to believe that if I did not understand English, I would not be able to persuade an English-speaker that I could speak English, no matter how many rulebooks I had. So I assume, in fairness, that I could not pretend to speak Chinese, with or without a rulebook, if I did not understand Chinese. Did Searle really suppose that he could speak passable Chinese if only he had a rulebook? Could you posit a Chinese with a rulebook who could pretend to speak English, without in fact understanding it? In other words, pose a corresponding "English Room puzzle" and you will see the fallacy. I am persuaded that any native, foreigner, machine, or simulation thereof, that can carry on a respectable conversation with me in English, must understand English. Incidentally, there is a language proficiency examination developed by Educational Testing Service, used in New Jersey (and other places, I suppose) to test the language qualifications of bilingual and ESL teachers, that might be adaptable for use in a Chinese Room trial. An interviewer converses with the subject to elicit speech in the test language on a variety of topics, and tapes the interview. A rater listens to the tape and judges how well the subject has succeeded in expressing ideas in the test language. The highest score, which would be attained by a native speaker with no trace of an accent, is 5. A subject with some accent, but full command of linguistic structure and demonstrable ability to discuss non-trivial topics, would be rated 4. I'd guess a machine or simulation with no semantic proficiency would score below 3 (but I'm not thoroughly familiar with the rating scale). So let me propose as a partial definition of "understanding": that anything that can score a 4 on the language proficiency examination must understand the language. M. B. Brilliant Marty AT&T-BL HO 3D-520 (201) 949-1858 Holmdel, NJ 07733 att!houdi!marty1 Disclaimer: Opinions stated herein are mine unless and until my employer explicitly claims them; then I lose all rights to them.
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/21/89)
sher@sunybcs.uucp (David Sher) of SUNY/Buffalo Computer Science, in a very revealing posting, asks: " what is the advantage of a machine with "understanding"? Assume that " HAL doesn't understand anything. He merely manipulates symbols so that " he creates an illusion of understanding in his correspondents. In what " way does that inhibit HAL as a useful tool? What could an " "understanding" machine [do] that a merely intelligent (the symbol " manipulator that merely gets the right answer) machine could not? " Unless someone can show me an advantage to it I'm not going to waste " much time designing it into my programs. There is no advantage to worrying about understanding if all you are interested in doing is making "useful tools" -- which is no doubt all that most of AI is interested in. One wonders, though, why a discipline with that motivation tries to push so hard on the repeatedly discredited "Systems Reply" to Searle, insisting that "The System" DOES understand, when the real goal is as superficial as this. Perhaps there is a confusion here between tool-making and mind-modeling. Cognitive psychologists, on the other hand, are interested in modeling the mind, including understanding, so we have no choice but to face the questions Searle (and the mind/body problem and the other-minds problem) raise. Searle's Argument simply shows that purely symbolic models are the wrong ones for our purposes. [Paradoxically, my own work suggests that even cognitive psychologists should not worry too much about capturing understanding: I have given reasons -- empirical, methodological and logical -- for adopting "methodological epiphenomenalism" and the "Total Turing Test (robotic version)" as constraints on cognitive modeling. However, these same reasons also go strongly against symbolic modeling in favor of hybrid modeling, grounding symbolic representations bottom-up in nonsymbolic (analog and categorical) representations.] Two other points: (1) You've got the assumption on the wrong foot: The default assumption is that HAL doesn't understand, not the other way round. You don't have to say "Assume Hal doesn't understand" any more than you have to say "Assume there are no fairies." The default "assumption" is no, unless compelling reasons are given for rejecting it. No compelling (or even coherent) reasons are coming from symbolic AI, and certainly not from proponents of the "Systems Reply." (2) Unless you are willing to think deeply on these questions you certainly ARE wasting your time "designing it [?]" into your programs! One of the reasons I think it's important to get these matters straight is because if you don't, you spend more time over-interpreting what your models are doing than in actually strengthening their performance capacity. This is a deep and subtle point. The Total Turing Test is the methodological goal. Hermeneutics and hyperbole about the "mental powers" of toy models is not the way to get there; it's just a way of covering up how pathetically far away from the goal we really are. -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/21/89)
lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii writes:
" You know that the other-minds issue is unresolvable, yet you suppose
" that you have resolved it when you premise your remarks on Searle (and
" others) having a mind. Someone is confused.
There IS an ordinary, everyday practical "solution" to the other-minds
problem, and that is what motivates my "Total Turing Test" (TTT): If
you can't tell the candidate apart from a person in any respect, in
terms of either its robotic or its linguistic performance capacity,
then you have no better or worse grounds for assuming it has a mind
than you have with any other person but yourself. Now that's only a
practical "solution," not a real solution or a guarantee. I'm certainly
willing to give Searle the benefit of the doubt here, because he can
pass the TTT, whereas the (hypothetical) symbol manipulator can only
pass the linguistic version.
But all of that is irrelevant anyway, because in the Chinese Room there
is first-person evidence available that there's NO Chinese
understanding going on in there -- exactly the same kind of
first-person evidence that makes one candidate (and one only) exempt
from the other-minds problem, namely, oneself: For you or I could do
Searle's simulation ourselves, and still not understand Chinese. We
don't need Searle; nor do we have to make any assumptions about his
having a mind!
Again, this is no guarantee; after all, someone ELSE in there could be
understanding, or even confused: The walls could have not only ears,
but a soul. There are, after all, two extreme conclusions one could
draw from the other-minds problem (both erroneous and far-fetched, in
my view): One is that because you can't confirm it for sure, therefore
NO ONE BUT YOU in fact has a mind. The other is that because you can't
disconfirm it for sure, EVERY THING [animate and inanimate, great and
small, part and whole) has a mind. I think neither of these conclusions
is satisfactory, and certainly neither follows as a matter of necessity
from the existence of the other-minds problem.
A third (and I think reasonable) conclusion from the other-minds
problem is to reserve the benefit of the doubt to candidates, like
ourselves, who pass the TTT. Not so confusing, I think...
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771yamauchi@cs.rochester.edu (Brian Yamauchi) (02/21/89)
In article <Feb.19.18.25.26.1989.15723@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >[This is the negative note on which Searle's Argument ended in 1980; >not to leave it at that, let me add that in "Minds, Machines and >Searle" (1989) I've tried to take it further in a positive direction, >showing that it's only the symbolic approach to modeling the mind >that's vulnerable to Searle's Argument; nonsymbolic and hybrid >symbolic/nonsymbolic models are not. And in "Categorical Perception" >(1987) I have sketched how symbolic representations could be grounded >bottom-up in nonsymbolic (analog and categorical) representations. Now, >being immune to Searle's argument doesn't guarantee that a model has >captured understanding, of course (nor does it "effectively define" >understanding). But it does perhaps correct the misapprehension that >the validity of Searle's argument (and it IS valid) would entail that >NO model could understand; perhaps this misapprehension is behind the >strained, implausible and incoherent counterarguments people have tried >to float under the general banner of the "Systems Reply." You don't >have to give up on "systems". Just give up on purely symbolic systems.] >-- >Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu I have been following this discussion for a while, and so I decided to go and read Searle's "Minds, Brains, and Programs" in Mind Design. In this essay, Searle outlines his basic argument and then tries to argue against a number of the possible objections. I think that Searle *does* have a valid criticism of traditional, symbolic AI. On the other hand, many of his counterarguments trying to broaden this point seem to range from the unclear to the bizarre. The basic idea that symbol manipulation alone is not necessary for intelligence makes sense. To translate Searle's argument from the language of philosophy to the language of AI, consider what it means to understand the sentence "The dog chased the cat." Traditional AI would represent this as: dog(x) & cat(y) & chased(x,y) However, the program really has no idea what a dog is, what a cat is, or what it means from one thing to chase another. This, I believe, is the crux of Searle's argument. One could add a dog schema which said something like: dog is-a : animal (subtype : mammal, carnivore) environment : land legs : 4 tail : yes But, then the program still doesn't know what a land environment is, or what legs are, etc. The conventional counterargument is that the richness of the knowledge base determines the level of understanding. So one could add schemas for mammals and environments, and so forth. Of course, these would have to be defined in terms of other symbols, and so on and so forth. To a large extent this is what happens with human learning. We learn new concepts by relating them to things we already know. The *critical* difference, in my opinion, is that at some level all of our learned symbols are grounded in sensory experience. Most of us probably learned what a dog was by seeing one or by seeing a picture of one, not by reading a dictionary definition. We know that "chasing" refers to an activity that we have seen (on TV, at least, if not in person), rather than simply a construct of: chase(x,y) --> wants-to-catch(x,y) & wants-to-avoid(y,x) Therefore, in order to build a system that "understands" in the same way that people "understand", we need to give it the ability to relate the concepts in its knowledge base to sensory experiences. This is a similar to what Searle calls "The Combination Reply" -- that a complete robotic system with sensory perceptions and motor control (and possibly based upon neural networks) could be said to have "understanding". Searle admits (p. 296) : "I entirely agree that in such a case we would find it rational and indeed irresistable to accept the hypothesis that the robot had intentionality, as long as we knew nothing more about it." But then, he goes off and says that since we know how the robot works, we can't ascribe "intentionality" to it. He says we *can* ascribe "intentionality" to animals because (1) We don't understand how they work and (2) They are made out of the same stuff as humans. This is almost too absurd to contemplate. (1) is equivalent to arguing that since primitive man couldn't explain the weather without refering to magic, storms must be the result of sorcery. (2) is nothing more than a form of vitalism which might be understable if Searle were a mystic, but is all the more baffling since he states (p. 300) the materialist position that humans are, in fact, machines that think. Searle goes so far as to state "Whatever else 'intentionality' is, it is a biological phenomenon and it is as likely to be causally dependent on the specific biochemistry of its origins as lactation, photosynthesis, or any other biological phenomena." One can only wonder what would happen if it were discovered that some humans depend more heavily on some neurotransmitters than others. Who would Searle consider non-intentional: the people using the non-standard neurotransmitters or whoever was using neurotransmitters that were different from his own? _______________________________________________________________________________ Brian Yamauchi University of Rochester yamauchi@cs.rochester.edu Computer Science Department _______________________________________________________________________________
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/21/89)
The careful reader will find an uncanny resemblance between the logic underlying the following exchange and Lewis Carrol on Achilles and the Tortoise (in which Carroll showed that you can lead someone to logical water, but there's no way to make him drink it). Read on: engelson@cs.yale.edu (Sean Engelson) of Computer Science, Yale University, New Haven, CT 06520-2158 asks: " What is your criterion for determining which is which [understanding " or not understanding Chinese]? As I said before, you need no definitions, no criteria. You only need to be able to tell the difference -- in your own, subjective, first-person case -- between when you understand a language (e.g. English) and when you do not (e.g., Chinese). Can you do that? Now please assume that Searle can do the same, and that he says he does NOT understand Chinese. There is no reason whatever (apart from the preconceptions that Searle's Argument was formulated to invalidate) (a) not to believe him or (b) to believe that there is "someone/something" else in the Chinese Room that IS understanding Chinese in the same sense that you or I or Searle understand English. To pick (b) merely on the basis of the preconceptions that are the very ones under criticism here is simply CIRCULAR. -- Now none of this is new; one would have thought that it would be clearly understood (sic) from my prior posting. Read on. " And I can equally well POINT to Searle running his rules for Chinese, " and say to (him + rules) in Chinese, "Look, you understand Chinese, " don't you?" and I'd expect to get back the answer (in Chinese) "Yes". In saying you could point to it, I was clearly speaking about the subjective phenomenon (i.e., whether YOU YOURSELF understand English or Chinese), which is primary and not open to doubt, rather than to its external manifestations (i.e., whether SOMEONE ELSE does): The evidential status of those external manifestations is precisely what's on trial here; one can't win this case by simply declaring them "judge and jury" instead! That's not a logical supporting argument; that's just circularity. " for all external intents and purposes, (Searle + rules) understands " Chinese... [whereas] "plain" Searle does not understand Chinese, " (Searle + rules) does not. Why not? What's the difference? The difference is that the "external" criteria have not been shown to be valid, and hence there is simply no justification for taking them to signal the presence of understanding at all. To merely assume that they do is not an argument; its just circularity again. For all external purposes, we have a (hypothetical, perhaps even impossible) situation in which a guy (imagine it's you) is running around manipulating symbols and saying he can't speak Chinese and has no idea what the symbols mean; meanwhile, ex hypothesi, if a Chinese person reads the symbols, they say "I understand Chinese... etc." Even if we accept the unlikely hypothesis that this is possible (and could go on for a lifetime, with the symbols as consistently lifelike and convincing as a real-life Chinese pen-pal), there's still no one around about whom we could say, "Ya, well if he says he understands, I'm ready to believe he understands, just I am about anyone else who says he understands." The only one around is you, and you say (don't you?) that you don't understand. Perhaps we should ask the hypothetical Chinese alter ego to say where he is, and where he stands on the matter... Part of the problem is of course with the premise itself (i.e., supposing that we could do all this with just symbols), which may be about as realistic as supposing that we could trisect an angle with just compass and straight-edge. All that the premise seems to do is to spuriously mobilize our instincts to defend the personhood of our unseen pen-pals. But recalling that there's no way we can be sure about our pen-pals under such conditions either, and that the SOLE case of understanding we can be sure about is still our very own (i.e., the "other minds problem"), ought to be a good antidote for mistaking external signs for the real thing even under such counterfactual conditions. " In other words, you are DEFINING understanding to be that which Searle " has with respect to English, and not that which (Searle + rules) has " with respect to Chinese. OK, given that distinction, tell me either " how I can distinguish between the two in a Turing-test fashion, or " what it is about Searle that allows him to understand English which " (Searle + rules) does not have. Otherwise, as I've said, I'll grant " you your point, and then say that this whole discussion is pointless, " as your concept of understanding is "That which people do", which is " useless. Have we made any progress here? I think not. I keep saying I'm not defining but pointing to a subjective experience that all people have and Engelson keeps talking about fanciful things that "people plus rules" have. Now he says that all this logical, methodological and empirical discussion, which was originally intended to assess the evidential status of the (teletype version) of the Turing test is now answerable to that test A PRIORI! That's like saying: "Well if God didn't create the earth, then tell me how he created Darwinian Evolution?" Preconceptions manage to survive without ever becoming negotiable! The only other possibility Engelson seems ready to imagine is a complete alternative causal/functional explanation of understanding that distinguishes Searle from a mere symbol-manipulator; but I've already said that we're far from such an account, nor do we need one for present purposes. Logically speaking, you just have to show that a theory is internally inconsistent or inconsistent with the data in order to show it's wrong (although Kuhn will of course remind you that that's not enough to make people give it up). You don't have to come up with the right theory. (If you want a better candidate in this case, though, try grounded hybrid robotic systems, as I've suggested.) Searle's denial that he understands Chinese (or your own denial, if you were in his place and had not yet been at Yale-CS too long to be able to call a spade a spade) seems like a big enough inconsistency to do in the purely symbolic theory. My "concept of understanding" is no different from what yours was before you bought into a fantasy that "a person plus rules" could understand even if the person couldn't. And if you want an idea of just how pointless a discussion is when logical arguments are unavailing, read Lewis Carroll on Achilles and the Tortoise. But to go on like this is more like Schultz on Charlie Brown and the football... -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
yamauchi@cs.rochester.edu (Brian Yamauchi) (02/21/89)
In article <Feb.20.20.43.21.1989.15687@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >[Paradoxically, my own work suggests that even cognitive psychologists >should not worry too much about capturing understanding: I have given >reasons -- empirical, methodological and logical -- for adopting >"methodological epiphenomenalism" and the "Total Turing Test (robotic >version)" as constraints on cognitive modeling. However, these same >reasons also go strongly against symbolic modeling in favor of hybrid >modeling, grounding symbolic representations bottom-up in nonsymbolic >(analog and categorical) representations.] >Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu I'm trying to figure out whether you and I are saying exactly the same thing, but using completely different languages. I'm saying that I agree with Hans Moravec and Rodney Brooks that in order to build intelligence, we will need to build complete robotic systems including both sensory input and motor control. Is this anything like "methodological epiphenomenalism"? _______________________________________________________________________________ Brian Yamauchi University of Rochester yamauchi@cs.rochester.edu Computer Science Department _______________________________________________________________________________
sher@sunybcs.uucp (David Sher) (02/21/89)
In article <Feb.20.20.43.21.1989.15687@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes (a bunch of stuff I agree with and then): > > ... > >There is no advantage to worrying about understanding if all you are >interested in doing is making "useful tools" -- which is no doubt all >that most of AI is interested in. One wonders, though, why a >discipline with that motivation tries to push so hard on the repeatedly >discredited "Systems Reply" to Searle, insisting that "The System" DOES >understand, when the real goal is as superficial as this. Perhaps >there is a confusion here between tool-making and mind-modeling. > > [ and more stuff that seems correct ] I'd like to hazzard an answer to this question. The reason the AI establishment tries to answer this question is there is a strong implication that Searle's argument indicates that symbolic AI approaches will always lack some performance capability. In fact what he seems to be arguing is that a symbolic AI system can have any desired capability but still lack "understanding". If Searle instead argued that AI systems will never possess a soul the argument would not be so strident yet the argument is identical (at least for the definition used in Jewish theology). But the word "understanding" is almost always associated with some performance criterion, thus Searles argument in denotation is unassailable (at least by the likes of me) but has incorrect connotations. I probably blew it, being far from an expert in rhetoric, but this seems to be the nub of the problem. Does anyone believe that they can build a machine with a soul? It is just as easy to build in Searle's "understanding." -David Sher ARPA: sher@cs.buffalo.edu BITNET: sher@sunybcs UUCP: {rutgers,ames,boulder,decvax}!sunybcs!sher
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/21/89)
marty1@houdi.ATT.COM (M.B.BRILLIANT) of AT&T BL Holmdel NJ USA adks: " Did Searle really suppose that he could speak passable Chinese if only " he had a rulebook? Searle inherited this premise from "Strong AI." His Argument only concerned what FOLLOWS from it. I'm sure Searle would be perfectly willing to doubt the premise (so would I), but that's beside the point. -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/21/89)
yamauchi@cs.rochester.edu (Brian Yamauchi) of
U of Rochester, CS Dept, Rochester, NY wrote:
" I agree with Hans Moravec and Rodney Brooks that in order to build
" intelligence, we will need to build complete robotic systems including
" both sensory input and motor control. Is this anything like
" "methodological epiphenomenalism"?
No, but it sounds like a step in the direction of the Total Turing Test
(TTT) rather than just the linguistic TT. It also sounds like a step
toward a grounded symbolic/nonsymbolic system, but it all depends on
the grounding scheme. Just hooking up an autonomous symbol-cruncher
module to autonomous transducer and effector modules won't do it; the
functional dependency of the symbols on the nonsymbolic representations
must be deeper and more intimate than that.
("Methodological Epiphenomenalism" is just a theoretical strategy that
recognizes that subjective phenomena cannot have an independent causal
role in a functional model and hence makes no direct attempt to
"capture" subjective phenomenology, just total performance capacity (TTT),
accepting that if mental processes are involved, they somehow
piggy-back on the functions generating the TTT capacity, and that there
is no way to confirm their presence directly except by BEING the robot
in question.)
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771harnad@elbereth.rutgers.edu (Stevan Harnad) (02/21/89)
vangelde@cisunx.UUCP (Timothy J Van) of Univ. of Pittsburgh, Comp & Info Sys wrote: " [2] is just the Physical Symbol System Hypothesis (Newell and Simon), " otherwise known as the GOFAI hypothesis (Haugeland). Is this really just " a bold [sic] claim that nobody would take seriously if they had thought deeply " about the issue? Is Harnad saying that Newell and Simon, Pylsyhyn, " Haugeland, Fodor etc have not thought deeply about the issue? Most of the individuals you mention are deep thinkers and have thought deeply about the issue. All of them are quite aware of the weaknesses of the hypothesis. I doubt that any of them would endorse the kinds of bald [sic] claims that many advocates of the "Systems Reply" to Searle have made. In my paper (JETAI 1 (1989) p. 23, fn. 24) I give what I think is close to an exhaustive list of the features that made "symbolic functionalism" (as I call it) look good for a while. The rest is devoted to showing why it was not good enough. -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
bwk@mbunix.mitre.org (Barry W. Kort) (02/21/89)
In article <16027@cisunx.UUCP> vangelde@unix.cis.pittsburgh.edu (Timothy J. van Gelder) questions the depth of Steven Harnad's thought processes: > If, by contrast, Harnad really has thought deeply about the issue, > he surely belongs in the ranks of Turing, von Neumann, Wittgenstein etc. Having read some of Steven's thoughts, I think it not unlikely that his name would be mentioned in the same sentence as Alan's, Johnny's, or Ludwig's. --Barry Kort
smoliar@vaxa.isi.edu (Stephen Smoliar) (02/21/89)
In article <764@htsa.uucp> fransvo@htsa.UUCP (Frans van Otten) writes: >In article <Feb.19.14.23.34.1989.8773@elbereth.rutgers.edu>, >harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >> >>The ONLY one who can know for sure that Searle has a mind is Searle himself. >>And the same is true of your mind: YOU know it (don't you? don't you?). > >You say you're *sure* that you have a mind, you *know* it. How can you >be *sure* if you only *know* it ? I say you only had a compile-time flag: > >program Stevan_Harnad(input, output); > >const I_HAVE_A_MIND = true; /* The main point */ > >var alive : boolean; > symbol : SymbolType; > result : ResultType; > >begin > alive = TRUE; > while alive > do > symbol = Read_Symbol; > result = Crunch_Symbol(symbol); > if result = dead > then alive = false > else Output_Result(result); > end; >end. > >I want you to show me how you can prove to yourself that you have a mind. >Until then I must assume that you are (only) a symbol cruncher, and so >must you. > I think Frans has done an excellent job of a symbolic reformulation of the point I originally wished to raise. An argument which is based on assertions of what it "obvious" to introspection is no argument at all, no matter how many words Searle and Harnad decide to invest in it. (Incidentally, I believe it was Harry Truman who coined a phrase to describe an argument which is supported by nothing more than an over-abundance of verbiage; he called it "The Big Lie.")
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (02/22/89)
From article <Feb.20.20.51.31.1989.15876@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): " ... " But all of that is irrelevant anyway, because in the Chinese Room there " is first-person evidence available that there's NO Chinese " understanding going on in there -- ... I can't agree to that, except as a terminological point. That is, if the program is to characterize the way 'understand' is ordinarily used, I have a limited sympathy with the argument. When we know the mechanism behind the behavior, we don't usually speak of 'understanding'. But even as mere linguistics, it's second rate, since when one chooses not to think or talk in terms of mechanism, 'understand' is still often appropriate. And we do develop new usages in the course of a conversation, as here when some come to be willing to attribute understanding to the Chinese room. Philosophers doing second-rate linguistics can be trying. Greg, lee@uhccux.uhcc.hawaii.edu
engelson@cs.yale.edu (Sean Engelson) (02/22/89)
In article <Feb.20.21.17.37.1989.16495@elbereth.rutgers.edu>, harnad@elbereth (Stevan Harnad) writes: > >The careful reader will find an uncanny resemblance between the logic >underlying the following exchange and Lewis Carrol on Achilles and >the Tortoise (in which Carroll showed that you can lead someone to logical >water, but there's no way to make him drink it). But, I suspect, that Harnad has the roles reversed. In any case, >Read on: >" What is your criterion for determining which is which [understanding >" or not understanding Chinese]? > >As I said before, you need no definitions, no criteria. You only need >to be able to tell the difference -- in your own, subjective, >first-person case -- between when you understand a language (e.g. >English) and when you do not (e.g., Chinese). Can you do that? Now >please assume that Searle can do the same, and that he says he does NOT >understand Chinese. However, the _system_ of (Searle + rules) says that it does understand Chinese. Is there some hidden reason (dare I say "criterion"?) to say that Searle knows what he's talking about, while (Searle + rules) does not? >There is no reason whatever (apart from the >preconceptions that Searle's Argument was formulated to invalidate) (a) >not to believe him or (b) to believe that there is "someone/something" >else in the Chinese Room that IS understanding Chinese in the same >sense that you or I or Searle understand English. To pick (b) merely on >the basis of the preconceptions that are the very ones under criticism >here is simply CIRCULAR. -- Now none of this is new; one would have >thought that it would be clearly understood (sic) from my prior >posting. In other words, you are a priori invalidating the systems approach. By this I mean the application of such terms as "understanding" et al. to the _entire_ entity under discussion, not merely the obvious, physical one. You seem to be denying the existence of (Searle + rules). Why? I don't see that the `paradox' inevitably leads one to deny this system existence; in fact it seems that your arguments take its NON-existence for granted. >Read on. > >" And I can equally well POINT to Searle running his rules for Chinese, >" and say to (him + rules) in Chinese, "Look, you understand Chinese, >" don't you?" and I'd expect to get back the answer (in Chinese) "Yes". > >In saying you could point to it, I was clearly speaking about the >subjective phenomenon (i.e., whether YOU YOURSELF understand English or >Chinese), which is primary and not open to doubt, rather than to its >external manifestations (i.e., whether SOMEONE ELSE does): The evidential >status of those external manifestations is precisely what's on trial >here; one can't win this case by simply declaring them "judge and jury" >instead! That's not a logical supporting argument; that's just >circularity. By this argument Searle _himself_ does not understand English, since all I have is his word, and since I cannot declare anyone but myself "judge and jury", I _must_ disbelieve him. Can you say "implicit solution to the Other Minds Problem"? I knew you could! >For all external purposes, we have a (hypothetical, perhaps even >impossible) situation in which a guy (imagine it's you) is running >around manipulating symbols and saying he can't speak Chinese and has >no idea what the symbols mean; meanwhile, ex hypothesi, if a Chinese >person reads the symbols, they say "I understand Chinese... etc." Even >if we accept the unlikely hypothesis that this is possible (and could >go on for a lifetime, with the symbols as consistently lifelike and >convincing as a real-life Chinese pen-pal), there's still no one around >about whom we could say, "Ya, well if he says he understands, I'm ready >to believe he understands, just I am about anyone else who says he >understands." The only one around is you, and you say (don't you?) that >you don't understand. Perhaps we should ask the hypothetical Chinese >alter ego to say where he is, and where he stands on the matter... Why do you assume that an intelligence must be 'person-like', in having a simple body which contains its underlying hardware and software. You seem to be making the hidden assumption that any system which is not `embodied', cannot understand. How do you justify this? >Part of the problem is of course with the premise itself (i.e., >supposing that we could do all this with just symbols), which may be >about as realistic as supposing that we could trisect an angle with >just compass and straight-edge. All that the premise seems to do is to >spuriously mobilize our instincts to defend the personhood of our >unseen pen-pals. But recalling that there's no way we can be sure about >our pen-pals under such conditions either, and that the SOLE case of >understanding we can be sure about is still our very own (i.e., the >"other minds problem"), ought to be a good antidote for mistaking >external signs for the real thing even under such counterfactual >conditions. Well, then, how does non-symbolism solve the other minds problem? How do I know that someone else understands through non-symbolic means, when symbolic do not suffice? If you argued that the other minds problem was insoluble, that would be fine, but you seem to be making the rather strong claim that it is solvable, given the proper non-smbolic representation. I see no substantiation of this claim, is there any? >Have we made any progress here? I think not. I keep saying I'm not >defining but pointing to a subjective experience that all people have How, please tell me, HOW can you point to a _subjective_ experience that someone other than yourself is experiencing? >and Engelson keeps talking about fanciful things that "people plus >rules" have. Now he says that all this logical, methodological and >empirical discussion, which was originally intended to assess the >evidential status of the (teletype version) of the Turing test is now >answerable to that test A PRIORI! Rather, I am arguing, that failing an answer to the other minds problem, this gedankenexperiment tells us nothing. A priori, there is no reason to distinguish between the evidence given us by Searle or by (Searle + rules), and this introduction of this nebulous subjective concept of understanding doesn't help much. >That's like saying: "Well if God >didn't create the earth, then tell me how he created Darwinian >Evolution?" Preconceptions manage to survive without ever becoming >negotiable! Rather more like saying, "How does Darwinian evolution _necessarily_ provide evidence against the existence of god?" >The only other possibility Engelson seems ready to imagine is a complete >alternative causal/functional explanation of understanding that distinguishes >Searle from a mere symbol-manipulator; but I've already said that we're >far from such an account, nor do we need one for present purposes. I would be satisfied for a descriptive account. How can I tell if someone or something understands Chinese or not? I'd like to know on what phenomenological basis you say that Searle understands while (Searle + rules) does not. I don't want a theory, just a criterion for reproducibility, so that I too may see the distinction. >Logically speaking, you just have to show that a theory is internally >inconsistent or inconsistent with the data in order to show it's wrong >(although Kuhn will of course remind you that that's not enough to make >people give it up). You don't have to come up with the right theory. But you do need some clear method of evaluating your data! From what I can tell, the data is identical in both cases, the difference being in the implementation. All I want is an evaluation criterion. (Is this getting repetitive? See the note at the top.) >seems like a big enough inconsistency to do in the purely symbolic >theory. Suppose that with the proper adjustment of an EEG machine, I was able to get Morse code (or some other linguistic phenomenon) out of my brain that said, in effect, "I do not understand English". Would you then say that _I_ do not understand English, ignoring my vehement replies to the contrary, and my demonstrated competence with the language? Well, Searle's denial of understanding is the same as my brain waves. Irrelevant. >My "concept of understanding" is no different from what yours was >before you bought into a fantasy that "a person plus rules" could >understand even if the person couldn't. I.e. you assume a priori the result that a person + rules cannot understand. The hidden assumption is revealed. ---------------------------------------------------------------------- Sean Philip Engelson, Gradual Student Who is he that desires life, Yale Department of Computer Science Wishing many happy days? Box 2158 Yale Station Curb your tongue from evil, New Haven, CT 06520 And your lips from speaking (203) 432-1239 falsehood. ---------------------------------------------------------------------- I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones. -- Albert Einstein
arm@ihlpb.ATT.COM (Macalalad) (02/22/89)
In article <Feb.20.21.17.37.1989.16495@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes:
[a long, condescending diatribe against Sean Engelson]
Stevan, I've tangled with you before, and I'll probably regret
doing it again, but there are a few issues that I want to address,
and I'd love to hear your response.
1. The distinction between Searle and (Searle + rules)
As I understand from your previous postings, you argue that
(Searle + rules) = Searle. The systems' argument, as I understand
it, argues that (Searle + rules) > Searle. I, of course, tend to
agree with the systems' argument, which seems more reasonable and
intuitive to me. After all, (Searle + rules) is fluent enough to
converse with a native Chinese speaker, whereas Searle can't even
begin to speak Chinese. Even further, I would guess that if
Searle internalized those rules, he _would_ be able to speak
Chinese!
The point is that this distinction is far from being trivial or just
a matter of preconceptions, and I think you need a stronger argument
than appealing to the common sense of the uneducated (or at least,
the pre-Yalie), making vague analogies to Darwin and evolution,
and hurling cheap insults at Sean Engelson.
As far as I can see, the way this problem is posed acknowledges the
difference between (Searle + rules) and Searle. After all, this
problem isn't interesting at all if we assume that (Searle + rules) =
Searle, since we know from the outset that Searle doesn't know
Chinese. Central to Searle's argument is the collapsing of this
distinction, which I think is fair game for criticism. No circular
reasoning, nothing up my sleeves.
2. Determining the understanding of (Searle + rules)
Now for the sake of argument, let's assume that there is a
distinction between Searle and (Searle + rules). If we all
acknowledge the other minds' problem, we can safely agree that
the only entity able to decide if (Searle + rules) really
understands Chinese is (Searle + rules). Not you or me or any
outside observers or even Searle himself. Only (Searle + rules).
The issue I now want to take up is your justification of the
Total Turing Test. As I understand it, you argue that it is
useful to assume that certain entities, specifically humans,
are intelligent and can interact with you in intelligent ways
that non-intelligent entities can't. If a robot (which I guess
would be (metal + rules), but that's a whole other kettle of fish)
can interact with you in such a way that you could not guess
that it was a robot, then it must be intelligent, too. Of
course, I can argue that this is a little too anthropocentric,
but the same argument can be made against the Turing Test, as well.
What I want to explore is the usefulness of the Total Turing Test.
I could argue that it would be just as useful to characterize
a system which could converse in a natural language as "intelligent"
and capable of "understanding" what I was saying, regardless of
whether it was right in front of me tap-dancing, or talking with
me via a computer terminal. Remember, Searle's arguments don't
really apply here, since this is a question of pragmatics, and not
a question of whether there really is any understanding taking place.
Of course, if you'd rather offer an objective definition of
intelligence and understanding, please feel free....
3. Conduct on the net
Now I understand that you are an important person with important
things to say, but that does not give you license to insult anyone
else, especially on such a public form as the net. We don't all
have the right answers, and often we don't even ask the right
questions. I see the net ideally as stimulating discussion, not
provoking mud slinging. If I said some things that were uncalled
for above, I apologize. I think that a few other apologies are
due.
'Nuff said.
-Alexmike@arizona.edu (Mike Coffin) (02/22/89)
From article <Feb.19.18.25.26.1989.15723@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): > Is anyone reading or understanding these postings? Or thinking about > what this is all about? As I've indicated repeatedly, this is NOT a > definitional issue! All I have to do is POINT to positive and negative > instances! [...] Oh fiddle. Science deals with the observable. That is the whole point of the Turing test --- if a box displays intelligence, then it is intelligent. If it seems to understand, it understands. There is no more point in differentiating between "understands" and "doesn't understand but seems to" than to differentiate between "orbiting because of gravity" and "being pushed by an undetectable angel that follows an inverse square law." If the box+rules seems to understand, then it understands. Pulling it apart and saying "this piece doesn't understand", "neither does this one", ... completely irrelevant. You might as well dissect a brain --- as you pull out each neuron you say "hmmmm... this clearly doesn't understand --- it is much too simple." Why is it so hard for some people to accept the fact that a system can have properties that none of its components have? -- Mike Coffin mike@arizona.edu Univ. of Ariz. Dept. of Comp. Sci. {allegra,cmcl2}!arizona!mike Tucson, AZ 85721 (602)621-2858
bwk@mbunix.mitre.org (Barry W. Kort) (02/22/89)
In article <4307@cs.Buffalo.EDU> sher@wolf.UUCP (David Sher) writes: > Does anyone believe that they can build a machine with a soul? Readers who are intrigued by this question may enjoy reading the two short pieces by Terrel Miedaner in _The Mind's I_ (Hofstadter and Dennett, 1981). --Barry Kort "Artificial Sentient Beings by the End of the Millenium!"
ray@bcsaic.UUCP (Ray Allis) (02/22/89)
>From: sher@sunybcs.uucp (David Sher) >Subject: Re: Question on Chinese Room Argument > >Now that we've posted megawords on "understanding" and whether a machine >can or can not posses it, can I ask: what is the advantage of a >machine with "understanding"? Assume that HAL doesn't understand >anything. He merely manipulates symbols so that he creates an illusion >of understanding in his correspondents. In what way does that inhibit >HAL as a useful tool. What could an "understanding" machine that a >merely intelligent (the symbol manipulator that merely gets the right answer) >machine could not? Unless someone can show me an advantage to it I'm not >going to waste much time designing it into my programs. > >-David Sher >ARPA: sher@cs.buffalo.edu BITNET: sher@sunybcs >UUCP: {rutgers,ames,boulder,decvax}!sunybcs!sher > Of course if the symbol manipulator "gets the right answer", the answer to your question is "There IS no difference!" I am one of those who doubt, however, that it is possible for either a person or a machine to "manipulate[s] symbols so that he creates an illusion of understanding in his correspondents". I don't think the Chinese Room could fool a perceptive human for very long. "Understanding" language is (at base) the evocation of experience in the receiving organism. Translation between languages requires language1-to-experience followed by experience-to-language2. You can't go directly from English symbols to Chinese symbols. Computers can't translate languages because they can't experience. (Yet.) Searle's Chinese Room is doing transliteration, and as pointed out by an earlier poster, rec.humor.funny just had several pages of hilarious examples of the results of that, e.g. a sign in a furrier's shop, "Here ladies can have coats made from their own skins". It might not always be funny. Understanding is more than language translation. Suppose I instruct a computer to "Eliminate crime in Detroit". It returns the next day with "Done! And it only took one 20 megaton device, Boss." *Lack* of understanding is THE major flaw in 30 years of "Physical Symbol System Hypothesis" AI.
vangelde@cisunx.UUCP (Timothy J Van) (02/22/89)
In article <Feb.21.00.20.44.1989.26600@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > >Most of the individuals you mention are deep thinkers and have thought >deeply about the issue. All of them are quite aware of the weaknesses >of the hypothesis. I doubt that any of them would endorse the kinds of >bald [sic] claims that many advocates of the "Systems Reply" to Searle >have made. > Does "All of them are quite aware of the weaknesses" mean (a) they dont really endorse the view; or (b) they are aware that there is some *apparently* contrary evidence. Surely (a) is false and (b) is true. These people really do think that we are essentially symbol manipulators, though they also think that some people believe otherwise for bad reasons, and also that the view *could* be wrong - after all, it is an empirical question. Your reply gives the misleading impression that many of the most ardent advocates of the physical symbol system hypothesis think that the view has "weaknesses, i.e. is not really true. In fact, in spite of practical difficulties in the way of demonstrating that it is true, they all wholeheartedly subscribe to it - and this despite having thought deeply about the issue. And its a good thing they subscribe to the view, too - otherwise we wouldnt have someone to disagree with (at least, someone who's *worth* disagreeing with to disagree with). Tim van Gelder c/o Dept of Philosophy University of Pittsburgh vangelde@unix.cis.pittsburgh.edu
rjc@aipna.ed.ac.uk (Richard Caley) (02/22/89)
In article <Feb.20.21.17.37.1989.16495@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >There is no reason whatever (apart from the >preconceptions that Searle's Argument was formulated to invalidate) (a) >not to believe him or (b) to believe that there is "someone/something" >else in the Chinese Room that IS understanding Chinese in the same >sense that you or I or Searle understand English. (a) is fine. (b) is, surely, a straw man. It is the homoculous argument again. Nobody is claiming there is "something else" in the room which understands chinese. There are two cases either 1) If something understands chinese then some sub part of it understands chinese. 2) not (1) Now the first is an infinite regress. If (1) is the case then nothing ( and noone ) can understand chinese. So it must be possible for something to "understand chinese" ( in our intuative sence ) without any sub part of it understanding. Hence (b) may not be the case, even allowing for a chinese understanding room. From this we can say that there are two extra cases in your above quoted argument c) There can be no such room. d) The room can understand chinese without any subpart ( searle pencil, paper, book of rules ) understanding. (c) is what searle is trying to prove, to do this he must disprove all other cases. He doesn't, as far as I can see eliminate (d). -- rjc@uk.ac.ed.aipna " Only love denies the second law of thermodynamics " - Jerry Cornelius
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/22/89)
lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii wrote: " I can't agree [that "in the Chinese Room there is first-person " evidence available that there's NO Chinese understanding going on in " there"] except as a terminological point... to characterize the way " 'understand' is ordinarily used... When we know the mechanism behind " the behavior, we don't usually speak of 'understanding'... when one " chooses not to think or talk in terms of mechanism, 'understand' is " still often appropriate. And we do develop new usages... as here when " some come to be willing to attribute understanding to the Chinese " room... Philosophers doing second-rate linguistics can be trying. There are two senses of "understand," a subjective and an objective one. The first (1) is what I mean when I say "I understand English" and the second (2) is what I mean when I say "He understands English." The first is primary. What I say and mean by "I understand" is based on direct, incorrigible, first-person evidence. When I say "HE understands," I am merely INFERRING that what's true of him is the same thing that's true of me when I understand. I can be WRONG (very wrong) about (2) but not about (1). It is (1) that is at issue in Searle's Argument, though people keep conflating it with (2). That's all there is to it. It's not a matter for linguists (any more than what I mean by "I am in pain" vs. "He is in pain" is). The only ones who worry about mechanisms here are cognitive modelers. And I am not a philosopher. -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (02/22/89)
From article <Feb.22.01.03.30.1989.19132@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): " ... " There are two senses of "understand," a subjective and an objective " one... No, there aren't. If there were, the one could not serve as antecedent for the other in identity-of-sense anaphora, as in 'He understands, and I do, too'. " I can be WRONG (very wrong) about (2) [objective] but not about " (1) [subjective]. ... If this were so, such a construction as 'I thought I understood, but I was wrong' would be self-contradictory. " And I am not a philosopher. Pardon me if I implied that only philosophers do second-rate linguistics. Greg, lee@uhccux.uhcc.hawaii.edu
marty@homxc.UUCP (M.B.BRILLIANT) (02/22/89)
From article <45126@linus.UUCP>, by bwk@mbunix.mitre.org (Barry W. Kort): > .... > In _Surely You're Joking, Mr. Feynman_, Richard Feynman recounts > an attempt to teach physics in Brazil. The students had become > very adept at formal symbol manipulation. They could regurgitate > the definitions and formulas, but they had no idea that the symbols > actually referred to anything in the outside world! I think this is a very significant observation. Feynman succeeded in determining that his students were not doing physics. Supposedly, they were not just trying to simulate an understanding of physics; they sincerely believed they understood physics. They fooled themselves, but they did not fool Feynman. This seems to show that the Chinese Room Argument fails in its premise, not in its logic. You cannot persuade a human observer that you are his or her equal if you are only manipulating symbols. If you assume you can, you will draw false conclusions. I think that proves something, but I'm not sure what. I think it proves that a system that passes the "Total Turing Test" (TTT) is not doing "mere symbol manipulation." I recall that the TTT is not formally defined. It is defined operationally, in terms of a received notion of a human observer. So any conclusion you draw from it is operational. Therefore, even if it provides an operational definition of "mere symbol manipulation," it brings us no closer to a formal definition. Same thing goes for "intelligence," "understanding," etc. Can we have a review of the question? What are we arguing about? M. B. Brilliant Marty AT&T-BL HO 3D-520 (201) 949-1858 Home (201) 946-8147 Holmdel, NJ 07733 att!homxc!marty Disclaimer: Opinions stated herein are mine unless and until my employer explicitly claims them; then I lose all rights to them.
gss@edsdrd.eds.com (Gary Schiltz) (02/23/89)
In article <45126@linus.UUCP>, bwk@mbunix.mitre.org (Barry W. Kort) writes: > > In _Surely You're Joking, Mr. Feynman_, Richard Feynman recounts > an attempt to teach physics in Brazil. The students had become > very adept at formal symbol manipulation. They could regurgitate > the definitions and formulas, but they had no idea that the symbols > actually referred to anything in the outside world! > My own similar first hand (and somewhat embarrassing to admit) experience: After I started college as an undergraduate in the mid 1970's, I took my first calculus course. Coming from a small high school in a small town, my math skills were minimal (a year or so of algebra), so the whole course was very confusing. In all the time I was in the course, I never did understand what calculus was all about. However, I did know, for example, that a derivative was "the equation you get when you manipulate another equation in such and such a way" and an integral was "the equation you get when you manipulate the equation in another way." I even had a fair amount of heuristic knowledge about how to solve word problems. "Hmm, that problem [on the exam] looks like the one we did in class. Let's see, first you take the derivative of this and plug in these numbers and solve for this variable, and then you circle the answer (and even if the answer is wrong, at least I can get partial credit for showing my work, and if everyone else is as confused as I am and they don't score well and the exam is graded on a curve, maybe I can pass)." I seemed to be able to do fairly good mapping of one problem to another based on its surface structure. Well, I did pass the course (now I'm ashamed that I didn't do what was necessary to understand what was going on, but like a lot of 17 year olds, I just took the easiest way). I later repeated the course and understood what I was doing (and made a lot better grade). Anyway, from my gut level feeling (quite possibly useless, I admit) about what understanding is all about, I really feel I had no understranding of calculus during that semester. Just as the Brazilian students didn't realize that symbols in physics equations actually referred to things in the outside world, I didn't know that the calculus was modelling anything. I truly had no idea that derivatives had anything to do with rate of change, for example. But, from the outside, it must have appeared that I had at least some understanding of calculus; at least I was good enough at manipulating equations to make the instructors think so. This really makes me wonder whether it can be determined whether or any system understands, simply from external behavior. I'm not trying to reach any conclusions about understanding, as I've not studied nor thought about it much. But, I thought it might be more food for thought. -- /\ What cheer, /\ | Gary Schiltz, EDS R&D, 3551 Hamlin Road | / o< cheer, <o \ | Auburn Hills, MI 48057, (313) 370-1737 | \\/ ) / cheer, \ ( \// | gss@edsdrd.eds.com | \ / cheer!!! \ / | "Have bird will watch ..." |
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/23/89)
rjc@aipna.ed.ac.uk (Richard Caley)
of Dept. of AI, Edinburgh, UK asks:
" If the argument ["showing that it's only the symbolic approach to
" modeling the mind that's vulnerable to Searle's Argument"] could be
" truncated to a reasonable length, then I would be interested if you
" posed it. I don't see why, say, searle in a room pulling strings and
" waving springs (or doing something else equally non-symbolic ) which
" happens to produce behaviour like a chinese speaker would not be the
" basis for a precicely parallel argument. I'm not saying you are wrong,
" just that it is not obvious.
Here it is, pp. 20-21 from Harnad, S. (1989) Minds, Machines and Searle.
Journal of Experimental and Theoretical Artificial Intelligence 1: 5-25.
See especially points (7) and (8):
Searle's provocative "Chinese Room Argument" attempted to show that the
goals of "Strong AI" are unrealizable. Proponents of Strong AI are
supposed to believe that (i) the mind is a computer program, (ii) the
brain is irrelevant, and (iii) the Turing Test is decisive. Searle's
argument is that since the programmed symbol-manipulating instructions
of a computer capable of passing the Turing Test for understanding
Chinese could always be performed instead by a person who could not
understand Chinese, the computer can hardly be said to understand
Chinese. Such "simulated" understanding, Searle argues, is not the same
as real understanding, which can only be accomplished by something that
"duplicates" the "causal powers" of the brain.
The following points have been made in this paper:
(1) Simulation versus Implementation:
Searle fails to distinguish between the simulation of a mechanism,
which is only the formal testing of a theory, and the implementation of
a mechanism, which does duplicate causal powers. Searle's "simulation"
only simulates simulation rather than implementation. It can no more be
expected to understand than a simulated airplane can be expected to
fly. Nevertheless, a successful simulation must capture formally all
the relevant functional properties of a successful implementation.
(2) Theory-Testing versus Turing-Testing:
Searle's argument conflates theory-testing and Turing-Testing.
Computer simulations formally encode and test models for human
perceptuomotor and cognitive performance capacities; they are the
medium in which the empirical and theoretical work is done. The Turing
Test is an informal and open-ended test of whether or not people can
discriminate the performance of the implemented simulation from that of
a real human being. In a sense, we are Turing-Testing one another all
the time, in our everyday solutions to the "other minds" problem.
(3) The Convergence Argument:
Searle fails to take underdetermination into account. All scientific
theories are underdetermined by their data; i.e., the data are
compatible with more than one theory. But as the data domain grows, the
degrees of freedom for alternative (equiparametric) theories shrink.
This "convergence" constraint applies to AI's "toy" linguistic and
robotic models too, as they approach the capacity to pass the Total
(asymptotic) Turing Test. Toy models are not modules.
(4) Brain Modeling versus Mind Modeling:
Searle also fails to appreciate that the brain itself can be understood
only through theoretical modeling, and that the boundary between brain
performance and body performance becomes arbitrary as one converges on
an asymptotic model of total human performance capacity.
(5) The Modularity Assumption:
Searle implicitly adopts a strong, untested "modularity" assumption to
the effect that certain functional parts of human cognitive performance
capacity (such as language) can be be successfully modeled
independently of the rest (such as perceptuomotor or "robotic"
capacity). This assumption may be false for models approaching the
power and generality needed to pass the Turing Test.
(6) The Teletype Turing Test versus the Robot Turing Test:
Foundational issues in cognitive science depend critically on the truth
or falsity of such modularity assumptions. For example, the "teletype"
(linguistic) version of the Turing Test could in principle (though not
necessarily in practice) be implemented by formal symbol-manipulation
alone (symbols in, symbols out), whereas the robot version necessarily
calls for full causal powers of interaction with the outside world
(seeing, doing AND linguistic competence).
(7) The Transducer/Effector Argument:
Prior "robot" replies to Searle have not been principled ones. They
have added on robotic requirements as an arbitrary extra constraint. A
principled "transducer/effector" counterargument, however, can be based
on the logical fact that transduction is necessarily nonsymbolic,
drawing on analog and analog-to-digital functions that can only be
simulated, but not implemented, symbolically.
(8) Robotics and Causality:
Searle's argument hence fails logically for the robot version of the
Turing Test, for in simulating it he would either have to USE its
transducers and effectors (in which case he would not be simulating all
of its functions) or he would have to BE its transducers and effectors,
in which case he would indeed be duplicating their causal powers (of
seeing and doing).
(9)
Symbolic Functionalism versus Robotic Functionalism:
If symbol-manipulation ("symbolic functionalism") cannot in principle
accomplish the functions of the transducer and effector surfaces, then
there is no reason why every function in between has to be symbolic
either. Nonsymbolic function may be essential to implementing minds and
may be a crucial constituent of the functional substrate of mental
states ("robotic functionalism"): In order to work as hypothesized
(i.e., to be able to pass the Turing Test), the functionalist
"brain-in-a-vat" may have to be more than just an isolated symbolic
"understanding" module -- perhaps even hybrid analog/symbolic all the
way through, as the real brain is, with the symbols "grounded"
bottom-up in nonsymbolic representations.
(10) "Strong" versus "Weak" AI:
Finally, it is not at all clear that Searle's "Strong AI"/"Weak AI"
distinction captures all the possibilities, or is even representative
of the views of most cognitive scientists. Much of AI is in any case
concerned with making machines do intelligent things rather than with
modeling the mind.
Hence, most of Searle's argument turns out to rest on unanswered
questions about the modularity of language and the scope and limits of
the symbolic approach to modeling cognition. If the modularity
assumption turns out to be false, then a top-down symbol-manipulative
approach to explaining the mind may be completely misguided because its
symbols (and their interpretations) remain ungrounded -- not for
Searle's reasons (since Searle's argument shares the cognitive
modularity assumption with "Strong AI"), but because of the
transdsucer/effector argument (and its ramifications for the kind of
hybrid, bottom-up processing that may then turn out to be optimal, or
even essential, in between transducers and effectors). What is
undeniable is that a successful theory of cognition will have to be
computable (simulable), if not exclusively computational
(symbol-manipulative). Perhaps this is what Searle means (or ought to
mean) by "Weak AI."
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771bwk@mbunix.mitre.org (Barry W. Kort) (02/23/89)
In article <9359@megaron.arizona.edu> mike@arizona.edu (Mike Coffin) asks: > Why is it so hard for some people to accept the fact that a system > can have properties that none of its components have? While it is certainly possible (and even desirable) for a system to exhibit emergent properties beyond the properties of the component parts of the system, our daily experience with politics and bureaucracy continues to remind us that large systems are considerably less functional than one would naively expect. --Barry Kort
bwk@mbunix.mitre.org (Barry W. Kort) (02/23/89)
Permit me to inject another anecdote into the discussion regarding the inadequacy of symbol manipulation. Recall the breakthrough scene in the Helen Keller Story. Helen's tutor has trained the recalcitrant child in finger-signing. Helen can manipulate the finger-sign symbols mechanistically, but she still doesn't communicate. Then while walking in the woods, Helen's tutor plunks the girl's hand into a cold flowing stream and signs "w-a-t-e-r". Suddenly Helen understands. Helen discovers that all those symbol sequences turn out to stand for something. The scene is about as moving as movies can get. The Chinese Room is like Helen before her moment of epiphany. There is little point in manipulating symbols mechanistically unless one can map the symbols to non-symbolic sensory information from the external world. In the modern world, terrorists and diplomats alike also manipulate symbols to effect motor responses in the external world. But that's another discussion. --Barry Kort
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (02/23/89)
From article <Feb.22.15.20.26.1989.931@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad):
" ...
" (5) The Modularity Assumption:
" Searle implicitly adopts a strong, untested "modularity" assumption to
" the effect that certain functional parts of human cognitive performance
" capacity (such as language) can be be successfully modeled
" independently of the rest (such as perceptuomotor or "robotic"
" capacity). This assumption may be false for models approaching the
" power and generality needed to pass the Turing Test.
This seems to me correct, except I'm not sure we could say that the
modularity assumption for language is untested. The construction of
(putatively) complete grammars has been attempted, and since none have
come close to correctly describing a natural language, the evidence
that's in suggests the assumption is false.
On the other hand, the proposal or conjecture found elsewhere in
Stevan's discussions that finding a way to ground the symbols will lead
us somehow to a better theoretical understanding is unlikely to be
correct. I think. In saying why, I'd prefer the terms 'syntactic' for
the symbol manipulation approach and 'semantic' for grounding symbols
(but without intending to imply that theories customarily called
'semantic' are properly so called).
A reasonable way to rate the prospects of an analytic approach is to ask
(and answer) the question: what has it helped us find out? Looking at
the score for the last few years, and sticking to fundamental
discoveries, I make it syntax: 3, semantics: 0. The discoveries are:
(1) Movement constraints (Haj Ross) -- constituents cannot occur
"too far" from where they belong,
(2) Cross-over (Paul Postal) -- nominals cannot come on the wrong
"side" of coreferents,
(3) One per sent (Charles Fillmore) -- when nominals are classified
by role (agent, patient, ...) one finds at most one of each
role represented per clause.
(Disclaimer: probably few linguists would agree with my scoring.)
My conclusion is that semantics as currently conceived has not
gotten us anywhere, and probably never will.
Greg, lee@uhccux.uhcc.hawaii.edumatt@nbires.nbi.com (Matthew Meighan) (02/24/89)
In article <7586@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) writes: > . . . An argument which is based on assertions > of what it "obvious" to introspection is no argument at all Can you prove this, or is it just obvious to you? It seems to me that the assertion that only objectively-provable things are "true" is a totally subjective one, hence false by its own criteria. What evidence is there for this belief? >(Incidentally, I believe >it was Harry Truman who coined a phrase to describe an argument which is >supported by nothing more than an over-abundance of verbiage; he called >it "The Big Lie.") This falsely equates subjective experience with "nothing more than an over-abundance of verbiage." The two are not equivalent. Subjective experience, or perception, is certainly "more than verbiage." Anyway, I doubt very much that Truman was referring to anything remotely like the Chinese Room argument when he coined this phrase. -- Matt Meighan matt@nbires.nbi.com (nbires\!matt)
curry@hplchm.HP.COM (Bo Curry) (02/24/89)
Steven Harnad writes: > >There are two senses of "understand," a subjective and an objective >one. The first (1) is what I mean when I say "I understand English" and >the second (2) is what I mean when I say "He understands English." The >first is primary. What I say and mean by "I understand" is based on >direct, incorrigible, first-person evidence. When I say "HE >understands," I am merely INFERRING that what's true of him is the same >thing that's true of me when I understand. I can be WRONG (very wrong) >about (2) but not about (1). It is (1) that is at issue in Searle's >Argument, though people keep conflating it with (2). > >That's all there is to it. It's not a matter for linguists (any more >than what I mean by "I am in pain" vs. "He is in pain" is). The only >ones who worry about mechanisms here are cognitive modelers. >And I am not a philosopher. >-- I'll have to disagree that a speaker claiming "I understand X" is incorrigible in the same way as a speaker claiming "I am in pain". Dennet has written extensively, and compellingly, on this issue. When I was a graduate student (not in philosophy :-) I often encountered students who claimed, with perfect sincerity, that they understood thermodynamics. I was in a much better position than they to judge the truth of their claims. When I studied Latin, I often thought I understood a poem or passage (i.e. I had puzzled some meaniing out of it, which I believed corresponded to the author's intent), and was later (embarassingly) proved wrong. If the phrase "I thought I understood X" has any meaning, then it clearly must be possible to be wrong about one's own understanding. Compare "I thought I understood the menu (but was proved wrong when the waiter brought my order)" to "I thought the needle hurt, but I was wrong". The first sentence is perfectly sensible, whereas the latter sounds surreal. Pain is a much more elusive beast than understanding. It is also possible to come up with instances when one claims *not* to understand, yet is mistaken in that claim. This is a bit rarer, but seems to occur if the understander expects something subtler or deeper than is really there. For example, I may hear a joke, and not find it funny at all. I say "I don't get it". In fact, I have considered several possible interpretations, but rejected them on the grounds of non-humourousness. Later, it may prove that one of my rejected interpretations was in fact the "meaning" of the joke, so that I had really understood it, after all. I was misled by my (mistaken, in this case) expectation that a joke, when understood, will be funny. Conclusion: An objective test is the only reliable measure of the understanding of a system. If the system claims to understand X, but nonetheless fails the standard test, we are justified in rejecting its claim. There is no "incorrigibility" associated with understanding. All this is, of course, unnecessary to definitively refute the Chinese room "argument". As a previous poster pointed out, *Searle's* understanding or lack thereof is totally irrelevant, since he is merely a *component* of the room. Searle's argument (however deeply thought about) reduces to the claim that "The mechanism is understood, therefore there is no understanding", which is absurd on the face of it. Cheers, Bo "Think deep, dig hard" Curry curry%hplchm@hplabs.HP.COM
bwk@mbunix.mitre.org (Barry W. Kort) (02/24/89)
In article <125@arcturus.edsdrd.eds.com> gss@edsdrd.eds.com (Gary Schiltz) recounts his personal experience in "doing calculus" at age 17 without really understanding what it was all about. Gary concludes: > This really makes me wonder whether it can be determined whether any > system understands, simply from external behavior. I'm not trying to > reach any conclusions about understanding, as I've not studied nor > thought about it much. But, I thought it might be more food for thought. In Feynman's anecdote about the Brazilian physics students, he easily uncovered their lack of understanding when he asked them questions about the real-world phenomena which the physics lessons covered. Their blank stares revealed that they had made no connections between everyday experiences and the subject at hand. F = ma had nothing to do with getting up to speed on a bicycle. Ft = mv had nothing to do with a hitting a baseball. --Barry Kort
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/24/89)
lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii wrote:
" No, there aren't "two senses of "understand," a subjective and an
" objective one," [otherwise we couldn't say] 'He understands, and I do too'
As I've suggested already, this is simply not a linguistic matter. The
distinction I'm after is already there with "pain" (although we don't
have two senses of pain as we do of understanding -- the reason for
this will become clearer as we go on). Consider "I'm in pain and he is
too." Apart from the obvious fact that I don't mean he's in MY pain
(which is already a difference, and not a "linguistic" one but an
experiential and conceptual one), it makes sense to say "He SEEMS to be
in pain (but may not really be in pain)," but surely not that "I SEEM
to be in pain (but may not really be in pain)." (Please don't reply
about tissue damage, because that's not what's at issue here [I didn't
say "I seem to have tissue damage"] -- or about lobotomy, which may
very well change the experiential meaning of pain for me.) The
difference (for me) between my pain and his pain is that mine is
directly experienced (by me) and his is only inferred (by me) from his
behavior.
Now the case of "understanding" is quite similar, except that the
behavioral criteria for the inference are much more exacting -- so much
so that there I CAN say "I SEEM to understand (but may not
understand)." The reason I can say this is apparent upon a little
reflection, and provides further evidence that there is both an
objective and a subjective sense of understanding. Follow carefully:
When I say "I only SEEM to understand," I mean objective understanding,
not subjective, i.e., "I do feel a (subjective) sense of understanding but
I can't provide the behavioral evidence of objective understanding, so
I don't relly understand in the objective sense." Subjective understanding,
on the other hand, is as certain as subjective pain (which happens to
be the only kind of pain -- the objective side of pain is the
tissue-damage story, and we rightly don't call that "pain"). You can't
say "I only SEEM to feel a (subjective) sense of understanding (but
I don't realy understand in the subjective sense)" any
more than you can say "I only SEEM to feel pain (but not really)."
Another point: I said that subjective understanding was PRIMARY for
the issues about mind-modeling under discussion here. In the human case,
the subjective sense of understanding and the evidence for objective
understanding tend to swing together in the vast majority of instances.
The correlation between them is not perfect, as the problem cases
already discussed -- S without O and O without S in us -- indicate, but
this is not relevant because these occasional dissociations all occur
in US, in whom the primary S is not in doubt. Symbol crunchers can't be
granted minds on the strength of our occasional mental lapses!
Perhaps if people (or objects) habitually went around emitting coherent
glossolalic discourse in foreign languages ("speaking in tongues") that
they claimed (in English) not to understand, or if they emitted nothing
but jargonaphasia that they kept feeling fervently to be full of
meaning, things might look a little different, but that's not the way
it is; S and O are quite tightly coupled, and S is clearly primary. In
fact, in a world without S, what would it even MEAN to ask whether or
not an event or a performance by a device "really" involved O ("objective
understanding")? It seems to me all you'd have would be events and
performances that could be "interpreted" by people with S as being
instances of O. But why bother? And if there were no people with S at
all, the whole problem of O seems to vanish altogether, leaving only a
world of objects, events and performances. (To a methodological
epiphenomenalist like me, it's a profound puzzle why the world ISN'T in
fact like this -- why there should be any S at all.)
The foregoing, let me repeat, was not a "linguistic" analysis. I simply
tried to remind everyone about what we all mean by pain and understanding,
and on what experiences this is based. I have not had to be hypothetical
or paradoxical here. Everyone knows the difference between the subjective
sense of understanding in ourselves and the objective evidence of it in
ourselves and others; everyone knows the difference between understanding
English and not understanding Chinese. But watch the torrent of
strained sci-fi that is again going to well up by way of quarreling with the
obvious in subsequent postings...
" [No, it's not true that we can be] "WRONG (very wrong) about (2)
" [objective] but not about " (1) [subjective] [understanding].
" If this were so... 'I thought I understood, but I was wrong' would be
" self-contradictory.
As I said above, there are two senses of understanding, subjective and
objective. The above statement could be paraphrased: "I thought I
understood it in the objective sense; it turns out I only understood it
in the subjective sense," i.e., it only FELT AS IF I understood it.
But in Searle's room the ISSUE is whether there's any mind there
feeling understanding at all (or feeling anything, for that matter)
rather than just a body that's ACTING AS IF it understood (i.e.,
that can be interpreted -- or misinterpreted -- as understanding by
people who do have understanding).
Ceterum sentio: This is not a linguistic matter.
" Pardon me if I implied that only philosophers do second-rate linguistics.
I won't make the obvious repartee, but will just repeat that these are not
linguistic matters... [In a later posting Lee mixes up the syntax
of the (putative) symbolic "language of thought" -- whose existence and
nature is what is at issue here -- and the syntax of natural languages:
Not the same issue, Greg.]
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771ins_atge@jhunix.HCF.JHU.EDU (Thomas G Edwards) (02/24/89)
During the Chinese Room discussion, many have brought up the concept that sensory experience is the bottom rung of intelligence, i.e. cat->chased by dog next door->dog's name is Fred->first letter is "F"->"F" looks like the following sensory experience While we may question the validity of the above idea, I'd like to point out that an AI system does not need "real" sensory input in the sense of eyes, ears, etc., but can use internal enviromental models (i.e. block's world). This knowledge, though, needs to somehow be entered into the computer from outside, in the form of verbose description, or an algorithm (perhaps involving pseudo-random numbers) describing the enviroment. -Thomas Edwards NN's on CM-2's!
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (02/24/89)
In article <3305@uhccux.uhcc.hawaii.edu> lee@uhccux.uhcc.hawaii.edu (Greg Lee) writes: >From article <Feb.20.20.51.31.1989.15876@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): >used, I have a limited sympathy with the argument. When we >know the mechanism behind the behavior, we don't usually speak >of 'understanding'. Hence the linguistic fact in English (and French, German, Chinese etc? - comments please) that any mechanical process cannot possess understanding. It is a central feature of "understanding" that mechanical processes are not involved. Thus for computer-based reasoning, one must choose another word or run the risk of been seen as ignorant or, more likely, disingenuous. >And we do develop new usages in the course of a conversation, as here when >some come to be willing to attribute understanding to the Chinese room. Some new uses are just plain deviant or mistaken and die with the conversation. Take the software 'toolkit' which contains a) unconfigured components and not tools b) some parts of a system, not all of them (a kit is complete). For first-rate linguists, I presume that all new meanings are valid and do not represent some form of verbal dyslexia on the part of anyone who uses them uncritically? The same is true of the new and creative meanings developed within the AI subculture. If a computer system has understanding, then where does it lie? Mine's in that still small voice within - why do AI types have to disown their's? Why insist on being 'scientific' when it's quite clear that you can't be on these issues? -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
dave@cogsci.indiana.edu (David Chalmers) (02/25/89)
The discussion on Searle's Chinese room seems to be becoming very confused. (I could make some bad jokes about the 'understanding' of some of the participants, but I'll refrain.) I thought I'd try to clear up one of the main sources of confusion, the word "symbol." This word is being used to mean two different things: (1) A "symbol" is a formal object which corresponds to some HIGH-LEVEL, semantic concept in the real world. Typically the concept which it corresponds to is on the level of a _word_, say, as opposed to a microstructural level such as that of a neuron. versus (2) A "symbol" is any formal object which is manipulated by a computer program. What we take this symbol to correspond to may be as low-level or as high-level as we like, or we may decide that the question of what the symbol corresponds to is meaningless and unimportant. Sense (1) is the sense in which the word "symbol" is used most of the time in AI. Newell, Simon, Fodor et al are all supporters of the "Symbolic Paradigm", which essentially means that they claim that true AI could be achieved by a program which formally manipulates such high-level symbols. (I'll say that by "true AI" here I mean a program which displays intelligent behaviour, in order to forestall questions like "but is it really thinking?"). Many people these days dispute this claim. One of the main reasons is that denoting such high-level, complex and inherently semantic concepts by a rigidly syntactic formal object will never be able to capture the richness and flexibility of such concepts. In a sense, these formal symbols are brittle and empty, devoid of "meaning." This is clearly also the sense of "symbol" which people have been using when they speak of the difficulty of understanding Portuguese or physics or mathematics by using pure symbol manipulation rules. Despite the fact that with such rules one can reproduce vaguely competent behaviour, the rigidity of such rules can, I believe, always be detected by close questioning, or observation under new and unusual circumstances. The fact is that high-level concepts interact in far too rich and flexible a manner, and this richness could never be captured by a set of rules which manipulate concepts as chunks. So I say: with sense (1) of "symbol", even weak AI can never be achieved. It will be impossible to fully reproduce intelligent behaviour. Thus, with this sense of "symbol", I reject the PREMISE of Searle's argument; a formal symbol-manipulator could never even display what _looked_ like competent Chinese-speaking behaviour. Thus, of course I am with Searle here in saying that such symbol-manipulators could never have true (subjective) understanding. But for me it's not an issue, for I believe that such manipulators would never even LOOK as if they understood. If this was Searle's point, this would be fine. But Searle wants to claim more. Contrary to what Harnad implies, Searle is not only arguing against high-level symbol manipulators in the Newell/Simon/Fodor mould. He wants to say that NO computer program could ever be enough to have true (subjective) understanding, not even an incredibly complex and subtle program (such as a program that simulated a neural network the size of the brain.) To do this, Searle uses the word "symbol" in sense (2), where it can denote any formal object whatsoever that is manipulated. The symbol can correspond to something as low-level as a neuron, or it may correspond to something which on the face of it has no meaning to us whatsoever. Presumably in a neural-net-simulator, a symbol corresponds to a neuron or one of its constituent parts - not a very 'semantic' object at all! But here is Searle's trick, or to be charitable (or uncharitable?) his mistake. He uses the word "symbol" in the low-level sense (2), while appealing to our intuitions about symbol-manipulators which manipulate high-level symbols of sense (1)! He says, (paraphrasing), "such a formal manipulator could never capture the SEMANTICS of the world to which the symbols correspond." What he implies here is that the symbols correspond to objects which have meaning, but that formal manipulation can never capture that meaning. (Just as those Brazilian physics students manipulated equations without anyone knowing what they _meant_.) But AHA - here we have him. These low-level (sense 2) symbols never had much meaning anyway! They correspond to micro-structural entities (such as neurons), which taken alone are devoid of semantics. Semantics only emerges when we put enough of these neurons together to form an incredibly complex SYSTEM. In a precisely similar way, semantics (and hence understanding) will arise from our sense-2-symbol-manipulator, when it has enough of these low-level symbols interacting in the right, incredibly complex way. Despite the fact that the symbols taken alone are meaningless, put enough of them together in the right way and meaning will be an EMERGENT property of the system, just as it is with the human brain. So this is the source of Searle's mistake. He appeals to our intuitions about high-level (sense 1) symbol-manipulators, and tries to use this to draw conclusions about low-level (sense 2) symbol manipulators. And by doing this he fails to appreciate the incredible complexity and subtlety that is possible in a sense-2-manipulator, from which understanding can be an emergent property, as it is in the human brain. It is a very mysterious question indeed how real understanding, subjective experience and so on could ever emerge from a nice physical system like the human brain, which is just toddling along obeying the laws of physics. But nevertheless we know that it does, although we don't know how. Similarly, it is a mysterious question how subjective experience could arise from a massively complex system of paper and rules. But the point is, it is the SAME question, and when we answer one we'll probably answer the other. I'll resist the temptation to answer each of Searle's other points one by one. Just remember, semantics CAN arise from syntax, as long as the syntactical system is complex enough, and involves manipulating micro-structural objects which interact in rich and subtle ways. So, for you neural-netophiles out there (as well as the rest of us fellow subcognitivists), there's hope yet! (Just keep the discussion of symbols on the right level.) Dave Chalmers Center for Research on Concepts and Cognition Indiana University
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/25/89)
dave@cogsci.indiana.edu (David Chalmers) of
Concepts and Cognition, Indiana University writes:
" ["Symbol"] is used [by Searle] to mean two different things:
" (1)... a formal object which corresponds to some HIGH-LEVEL, semantic
" concept in the real world... [e.g.,] a _word_ [and] (2)... any formal
" object... manipulated by a computer program... low-level or
" high-level [or meaningless] [e.g., a neuron]
So far, so good, though I don't find this distinction particularly
useful, because it just concerns how you INTERPRET the meaningless
symbols you're manipulating -- here as words, there as neurons. (In
principle, even the very same program could be interpreted either way.)
But let's go on and see where this leads:
" with sense (1)... I reject the PREMISE of Searle's argument; a formal
" symbol-manipulator could never even display what _looked_ like
" competent Chinese-speaking behaviour
Well, this certainly gives away the store, and I'm inclined to agree.
But I have reasons. Do YOU have better reasons than that you like neurons
better than words?
" [But] Contrary to what Harnad implies, Searle is not only arguing
" against high-level symbol manipulators in the Newell/Simon/Fodor mould.
" He wants to say that NO computer program could... have true
" (subjective) understanding, not even an incredibly complex and subtle
" program (such as a program that simulated a neural network the size of
" the brain.)
Actually, I don't imply otherwise: This is exactly what Searle would
say, because for him it is immaterial how the symbols are interpreted
by the programmer, as words or as neurons: To him they're all just
meaningless symbols. And so are the inputs and outputs (Chinese
symbols, remember? not Chinese neurons). Nor is Searle impressed
with hand-waving about "incredible complexity and subtlety": Symbol
manipulation is just symbol manipulation, no matter how complex the
symbols or the interpretations.
" [Searle] uses the word "symbol" in the low-level sense (2), while
" appealing to our intuitions about symbol-manipulators which manipulate
" high-level symbols of sense (1)!... But AHA - here we have him. These
" low-level (sense 2) symbols... correspond to micro-structural entities
" (such as neurons), which taken alone are devoid of semantics. Semantics
" only emerges when we put enough of these neurons together to form an
" incredibly complex SYSTEM. Despite the fact that the symbols taken
" alone are meaningless, put enough of them together in the right way and
" meaning will be an EMERGENT property of the system, just as it is with
" the human brain.
What we have here is exactly what it sounds like: Not an argument, but
a statement of faith in the "emergent" properties of "incredibly
complex" systems. I feel the same way about clouds sometimes.
The human brain's another story. (The following is almost a paraphrase
of some arguments from my paper, "Minds, Machines and Searle.") Of
course we know the brain "has" semantics. But a symbolic simulation of
a brain is not a brain, any more than a symbolic simulation of a plane
is a plane. Hence there's no reason to believe that a brain simulation
can think any more than a plane simulation can fly.
On the other hand, there is every reason to believe that a correct
brain simulation, like a correct plane simulation, could model
symbolically all of the relevant causal principles we would need to
know about thinking and flying in order to implement their mechanisms
as a brain and a plane, respectively. The implemented brain and plane
could then think and fly, respectively. But they wouldn't be just
symbols anymore either. For one thing, they'd have to have the causal
wherewithal for interacting with the outside world the way brains and
planes do -- and that's not just symbols-in and symbols-out. They would
have to include transducers and effectors (which, as I said before, are
immune to Searle's Argument), and, if the other arguments I've been making
have any validity, it would have to include a lot more nonsymbolic
(analog, A/D, feature-detecting, categorical, D/A) processes in between
the input and the output too.
As long as the system's of the right type, you need make no special
appeal to "incredible" complexity and "emergent" properties (though
it'll no doubt be complex enough). Where you need inordinate amounts of
complexity and equal amounts of credulousness is with a system of the
wrong type, such as a purely symbolic one (or perhaps a purely gaseous
one).
" It is a very mysterious question indeed how real understanding,
" subjective experience and so on could ever emerge from a nice physical
" system like the human brain... nevertheless we know that it does,
" although we don't know how. Similarly, it is a mysterious question how
" subjective experience could arise from a massively complex system of
" paper and rules. But the point is, it is the SAME question, and when we
" answer one we'll probably answer the other.
The first case is certainly a mystery that is thrust upon us by the
facts. The second is only a mystery if we forget that there are no facts
whatsoever to support it, just the massively fanciful overinterpretation of
meaningless symbols.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771mmt@client1.dciem.dnd.ca (Martin Taylor) (02/26/89)
--
--There are two senses of "understand," a subjective and an objective
--one. The first (1) is what I mean when I say "I understand English" and
--the second (2) is what I mean when I say "He understands English." The
--first is primary. What I say and mean by "I understand" is based on
--direct, incorrigible, first-person evidence. When I say "HE
--understands," I am merely INFERRING that what's true of him is the same
--thing that's true of me when I understand. I can be WRONG (very wrong)
--about (2) but not about (1). It is (1) that is at issue in Searle's
--Argument, though people keep conflating it with (2).
--
--That's all there is to it. (Stevan Harnad)
You may perhaps be correct of yourself when you claim "I understand English"
but you cannot know you are correct when you say "I understand what you
just said in English" even though your subjective impression is that you
understood. You therefore cannot claim "I understand statements written
(spoken) in English," which I think is close to what "I understand English"
means. The best you can do, I think, is to go by analogy to Harnad's
arguments on categorization--behaviourally your responses to statements
in English have usually had the expected effect on the person making the
statement, so you interpret the feedback as indicating that you did indeed
understand. Just as miscategorization is determined by unexpected feedback
from the world, so misunderstanding is determined by unexpected feedback
from a communicating partner. You cannot, by yourself, determine that
you understand. It's just a feeling, untested.
There is a close analogy in psychophysics. Ask someone "Did you hear that
tone" and you will get an answer that (presumably) corresponds to the
subjective experience of hearing the tone. But put them in an experiment,
in which they must determine which of two intervals contained the test tone,
and they will get moderately high scores, well above chance, under conditions
in which they may say "I didn't hear more than two or three of those."
Similarly, in experiments in which they must say simply whether a tone
was in a single interval, they will say "Yes" on many intervals in which
a tone was not presented. The subjective impression does not correspond
to the objective event of hearing, any more than the subjective impression
of understanding corresponds to the objective event of understanding.
--
Martin Taylor (mmt@zorac.dciem.dnd.ca ...!uunet!dciem!mmt) (416) 635-2048
If the universe transcends formal methods, it might be interesting.
(Steven Ryan).thom@dewey.soe.berkeley.edu (Thom Gillespie) (02/26/89)
For what it matters: Stephen Mitchell is a noted translator who recently was interviewed on NPR about his new translation of the "TAO". The translation is beautiful and clear and Stephen Mitchell does not speak Chinese , his Master suggested that it wan't important and suggested that he just use a dictionary and follow his instincts for making sense. Granted he referred to previous works but for the most part he just looked for a good meaning and gave it good "context" e.g. bombs and money instead of swords and gold.Stephen Mitchell definitely needed a context , an experience of the world , which computers don't have and more importantly don't need. The TAO that can be told is not the true TAO The God that can be named is not the true God -- TAO Thom Gillespie
geddis@polya.Stanford.EDU (Donald F. Geddis) (02/26/89)
In article <45199@linus.UUCP> bwk@mbunix.mitre.org (Barry Kort) writes: >The Chinese Room is like Helen [Keller] before her moment of epiphany. >There is little point in manipulating symbols mechanistically >unless one can map the symbols to non-symbolic sensory >information from the external world. That might be true if the issue were learning. In the case of Searle's Chinese Room argument, however, we are already *assuming* that the system is capable of communicating like a native speaker. The system already acts as though it connected the symbols to their non-symbolic referents. Note how easy it was to know that Helen Keller did *not* understand the connection: almost any simple "conversation" gave it away. Now it might be true that a computer system could not converse intelligently without being embodied in the real world. But the real question Searle considered was: How do you determine when a system is intelligent, when it actually thinks? The AI answer is "treat it as a black box and observe its behavior (have conversations, in this case)". Searle (mistakenly) disputes this view, and wants us to look inside the system for some "causal powers". -- Don-- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
geddis@polya.Stanford.EDU (Donald F. Geddis) (02/26/89)
In article <45213@linus.UUCP> bwk@mbunix.mitre.org (Barry Kort) writes: >In article <125@arcturus.edsdrd.eds.com> gss@edsdrd.eds.com (Gary Schiltz) >recounts his personal experience in "doing calculus" at age 17 >without really understanding what it was all about. Gary concludes: > > This really makes me wonder whether it can be determined whether any > > system understands, simply from external behavior. >In Feynman's anecdote about the Brazilian physics students, he easily >uncovered their lack of understanding when he asked them questions >about the real-world phenomena which the physics lessons covered. >Their blank stares revealed that they had made no connections between >everyday experiences and the subject at hand. F = ma had nothing to >do with getting up to speed on a bicycle. Ft = mv had nothing to do >with a hitting a baseball. You wonder whether external behavior can tell you if the system understands. And yet in both these cases, the "proof" that the system (person) did not understand was simply external behavior. In calculus, the hardest questions were answered incorrectly. Gary said that his grade went up when he retook the class and "understood". And he even stated an example: The connection between a derivative and rates of change. It seems rather trivial to "externally" test this one with a single question. In Feynman's Brazil experience, he seemed to have little difficulty telling that his student's level of understanding was relatively shallow. Most questions that were not simple restatements of memorized phrases showed a lot of difficulty. Just because it requires careful probing and the examiner can be fooled, doesn't mean that "external behavior" is not the proper criteria for deciding when a system understands. Just what, exactly, is being proposed as an alternative test? -- Don -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
bwk@mbunix.mitre.org (Barry W. Kort) (02/26/89)
In article <45199@linus.UUCP> I wrote: > The Chinese Room is like Helen Keller before her moment of > epiphany. There is little point in manipulating symbols > mechanistically unless one can map the symbols to non-symbolic > sensory information from the external world. In article <7219@polya.Stanford.EDU> geddis@polya.Stanford.EDU (Donald F. Geddis) responds: > That might be true if the issue were learning. In the case of > Searle's Chinese Room argument, however, we are already *assuming* > that the system is capable of communicating like a native speaker. > The system already acts as though it connected the symbols to their > non-symbolic referents. Note how easy it was to know that Helen > Keller did *not* understand the connection: almost any simple > "conversation" gave it away. Donald, I think we have uncovered an important issue hidden in the Chinese Room debate. When I have a conversation with another intelligent being, I expect to exchange knowledge, such that we both understand more than we did before the conversation. That is, I cannot conceive an intelligent entity which does not engage in learning (knowledge acquisition). When I add a symbol (such as the word "colligate") to my personal lexicon, I also add its referent. Now when I sort through a jumbled collection of ideas, trying to put the pieces together, I can associate that activity with the word "colligation". Can the Chinese Room do that? > Now it might be true that a computer system could not converse intelligently > without being embodied in the real world. But the real question Searle > considered was: How do you determine when a system is intelligent, when it > actually thinks? The AI answer is "treat it as a black box and observe its > behavior (have conversations, in this case)". Searle (mistakenly) disputes > this view, and wants us to look inside the system for some "causal powers". I like this operational definition of intelligence. I also believe that if the candidate system were doing nothing more than formal symbol manipulation, I could unmask it as easily as Feynman unmasked the Brazilian physics students. Formal symbol manipulation is an important and useful tool for the cognitive computer, and any intelligent entity is well-advised to acquire such capacity. But any intelligent system who thereupon stops learning is doomed to be disparaged as lacking in a desirable quality: the ability to discover and report interesting new ideas. --Barry Kort
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/27/89)
geddis@polya.Stanford.EDU (Donald F. Geddis) of Stanford University writes (in a pair of successive postings): " it might be true that a computer system could not converse " intelligently without being embodied in the real world. But the real " question Searle considered was: How do you determine when a system " is intelligent...? The AI answer is "treat it as a black box and observe " its behavior (have conversations, in this case)". Searle (mistakenly) " disputes this view, and wants us to look inside the system for some " "causal powers"... Just because it requires careful probing and the " examiner can be fooled, doesn't mean that "external behavior" is not " the proper criteri[on] for deciding when a system understands. " Just what, exactly, is being proposed as an alternative test? There are two alternative OBJECTIVE tests for having a mind, the (standard) Linguistic Turing Test [LTT] (symbols-in, symbols-out) and my stronger (robotic) Total Turing Test (TTT) (proximal-projections-of- objects-on-sensors-in, effector-action-on-objects-out). The LTT is a subset of the TTT, but one that is, as I have indicated repeatedly, EQUIVOCAL about the issue of "embodiment" and the putative autonomy of symbolic function from many forms of nonsymbolic function that may be needed in order to pass the LTT in the first place. Searle is only addressing the LTT, and my reply to Searle is that the TTT is immune to his arguments against the LTT. Neither the TTT nor the LTT, however, provides a guarantee that the candidate has a mind. There is and can be no objective test for that, only a first-person subjective one: To perform that, you have to BE the candidate. ONLY this subjective test is decisive. There are two senses in which Searle is advocating "looking inside": One is to look at the functions of the brain, because we have pretty good reason to believe that candidates with brains have minds (because, as I would put it, candidates with brains can pass the TTT). The second sense of "inside" is the first-person test for subjectivity, which we can all perform on ourselves. It's THAT "causal power" that he reminds us brains have but symbol-crunchers do not. My reply is that candidates OTHER than the brain that can pass the TTT (if and when we come up with any) are immune to his Chinese Room Argument that they cannot have a mind (though, of course, I repeat, no objective test can demonstrate that anyone, EVEN ourselves, has a mind). Searle's argument against (hypothetical) candidates that pass the LTT only, with symbols only, is decisive, however. I've always thought this reasoning was quite easy to understand, but from the fact that very few people have given me any objective evidence that they've understood it, I've concluded that it must be difficult to understand. Maybe by trying to put it slightly differently each time, tailoring it to the latest misunderstanding, I'll succeed in making it understood eventually... -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
smoliar@vaxa.isi.edu (Stephen Smoliar) (02/28/89)
In article <230@nbires.nbi.com> matt@nbires.UUCP (Matthew Meighan) writes: >In article <7586@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) >writes: > >> . . . An argument which is based on assertions >> of what it "obvious" to introspection is no argument at all > >Can you prove this, or is it just obvious to you? > >It seems to me that the assertion that only objectively-provable >things are "true" is a totally subjective one, hence false by its >own criteria. What evidence is there for this belief? > TOUCHE! This is a well-turned argument, forcing me to retreat to reconsider what it was I REALLY meant! Ultimately, I am trying to get away from using the word "obvious" too carelessly; but in doing so I seem to have fallen into the same trap! So how can I get myself out of it? When we are discussing the physical sciences, I suspect that it is possible to talk about "obvious" manifestations of phenomena. (Note that these manifestations need not necessarily be veridical. Thus, it is "obvious" that one arc shape is larger than another, even if we can demonstrate that they are both identical.) What I REALLY wanted to object to is a tendency to hide behind a word like "obvious" when we are trying to discuss words like "understand." Thus, I would argue that the manifestation of intelligent behavior cannot be observed the way we observe the size of a physical object. I admit that this point is open to debate; but as long as we are debating it, we should probably lay off words like "obvious." >>(Incidentally, I believe >>it was Harry Truman who coined a phrase to describe an argument which is >>supported by nothing more than an over-abundance of verbiage; he called >>it "The Big Lie.") > >This falsely equates subjective experience with "nothing more than an >over-abundance of verbiage." The two are not equivalent. Subjective >experience, or perception, is certainly "more than verbiage." > This was not my point. I merely wanted to illustrate what one of my mathematics professors once called "proof by intimidation." We should know better than to invoke such arguments.
arm@ihlpb.ATT.COM (Macalalad) (02/28/89)
In article <17923@iuvax.cs.indiana.edu> dave@duckie.cogsci.indiana.edu (David Chalmers) makes the following distinction: >(1) A "symbol" is a formal object which corresponds to some HIGH-LEVEL, >semantic concept in the real world. Typically the concept which it >corresponds to is on the level of a _word_, say, as opposed to a >microstructural level such as that of a neuron. > >versus > >(2) A "symbol" is any formal object which is manipulated by a computer >program. What we take this symbol to correspond to may be as low-level >or as high-level as we like, or we may decide that the question of what >the symbol corresponds to is meaningless and unimportant. I'm not sure if this is a useful distinction. I'll grant that many AI programs deal with symbols at level (1), that perhaps people think only of symbols at level (1) when thinking about the Chinese room scenario, and even that Searle himself might have originally had level (1) in mind when he came up with the Chinese room scenario (although I doubt it). However, this distinction is not crucial to Searle's argument, and I don't think he appeals to our intuitions about symbols at level (1) to argue against symbols at level (2), as you seem to imply: >But here is Searle's trick, or to be charitable (or uncharitable?) his >mistake. He uses the word "symbol" in the low-level sense (2), while >appealing to our intuitions about symbol-manipulators which manipulate >high-level symbols of sense (1)! He says, (paraphrasing), "such a formal >manipulator could never capture the SEMANTICS of the world to which >the symbols correspond." What he implies here is that the symbols >correspond to objects which have meaning, but that formal manipulation >can never capture that meaning. No, what Searle is appealing to is our intuition that there is something more to understanding than just manipulating symbols around. He is arguing that we are something more than just mere formal systems, and that all formal systems, no matter what level their symbols are, lack something else, something essential to understanding. On the other side of the fence, we argue that formal systems are more powerful than what our intuitions lead us to believe. Understanding can "emerge" from a powerful enough formal system. Now we come to a standoff, with each side convinced that the other side is wrong. One of the problems is the Turing Test itself. The Turing Test is essentially a behavioral test which treats the system in question as a black box. The Turing Test judges the system solely on its behavior, without regard to how the system works. Because of this, the Turing Test is vulnerable to skeptical attacks such as Searle's. If we take behavior to be the only criteria for demonstrating understanding, someone can always make the argument that a system isn't really understanding, even if its behavior is very convincing. This eventually boils down to the other minds problem. On the other hand, Searle can't conclude that the Chinese room doesn't understand Chinese; he can only appeal to our intuitions about what can and cannot understand. Obviously, different people have different intuitions. Where do we go from here? There are several options: 1. Ignore Searle's attack and continue building AI systems which come closer and closer to behaving like a human. Unfortunately, unless the system is very, very good, it won't convince anyone that it's understanding, least of all Searle. 2. Acknowledge Searle's attack and build AI "tools" which have no claims to understanding. 3. Sidestep Searle's attack by "strengthening" the formal system. This could be done by adding analog states, sensory input/output, etc. However, if the ultimate criteria for understanding remains a behavioral one, then skeptical attacks like Searle's cannot be avoided. 4. Come to a better understanding of the process of understanding, and different criteria for judging a system than just a purely behavioral one. I think that the most satisfactory answer to Searle would be "This and that are what is involved in understanding, and the formal system in the Chinese room demonstrates (or fails to demonstrate) this and that here and there." I think that most good AI research is done under this category, where the emphasis is on understanding how the mind works, biologically, psychologically, and computationally. -Alex
cn6gr8au@ariel.unm.edu (James D. Nicholson ChNE) (02/28/89)
> >I suppose that it is technically true that everything done on a computer >can be reduced to the level of abstract symbol processing. To point to >this low level of computer processing and then to talk about the very >high level capabilities of the human brain and ask 'How can one be the other?' >is rhetoric of the very worst kind. But 'abstraction' is the creative conceptualization of perception on all levels! Computer processing is not abstract! Computers don't have concepts (yet); they don't get the general idea. They don't have ideas. >To begin with, it ignores the fact that >we can reduce the operations of the brain to a very low level and then show, >mathematically, that the computational capabilities of neurons and >computers are in fact equivalent. Can you reduce the functioning of water to the functioning of hydrogen and oxygen and then arrive at polar clusters?...NO! You wouldn't even get proper dielectric behavior. Enough reductionism. You imply the ultimate equivalence of the mind with a complicated pinball machine. If you can actually do this reduction, do it and become rich. >What Searle points to as evidence of >man's difference from machines are direct consequences of the incredibly >complex organization of these low level neurons, which has been achieved >only after billions of years of evolution. There is as yet no theorectical >reason why we cannot eventually learn to create similarly complex machines. >If we understood how neurons can be organized in such a way as to produce >cognitive functions such as 'understanding' or 'creativity', then we could >say exactly how 'one can be the other'. Producing such machines means recognizing that 'understanding' and 'creativity' are not UNIX utilities;--- they are not disjoint. Just as we have height and width together, the human mind utilizes the entire set of neural entities to continually recreate the instances of the central law which forms the mind in which all mental faculties exist together. (A long sentence, I realize. Summary: the mind exists as a single function.) In animals, the central law is different, but real. It learns things in terms of genetically encoded logics. Thus, the animal cannot discover its origins in the framework of creative logics. In either case, there exists a central law with all of its conjugated laws which constitutes an intangeable existence. The connections of neurons create logical pathways, not laws. 'Law' implies operation (i.e. thinking), while, logic is static and non-living. A law is intelligible and is discovered only through insight. Logic is merely relativistic and may be directly appropriated by a LISP machine. We are abstract thinkers, and as such, will think about these neural machines which will obey the laws of our individual existence in abstracto:--- can we conceive of the abstract as a juxtaposition of low-level logical options? And when we do, does that thought utilize old logic or create new logic? Clearly, the reductionist viewpoint on the equivalence of neural connections and mind cannot be truly conceived, since, it is itself progress towards a counterposition of true logics in an unresolved form. The conclusion is that there exist things other than logics which generate the logic of neurons. J.D. Nicholson
bwk@mbunix.mitre.org (Barry W. Kort) (02/28/89)
In article <9739@ihlpb.ATT.COM> arm@ihlpb.UUCP (Alex Macalalad) swallows Searle's criticism of strong AI and peers over the horizon: > Where do we go from here? There are several options: > > 1. Ignore Searle's attack and continue building AI systems which come > closer and closer to behaving like a human. Unfortunately, unless > the system is very, very good, it won't convince anyone that it's > understanding, least of all Searle. I'm not sure this is the direction we want to go. Human behavior is not a good example of intelligence or understanding. Humans are emotional, irrational, and error-prone. I think we should go in the direction of systems who are able to learn by scientific methods. > 2. Acknowledge Searle's attack and build AI "tools" which have no > claims to understanding. I am all in favor of building useful tools. Such undertakings are an excellent apprenticeship for those who would become pioneering contributors to the frontiers of AI. > 3. Sidestep Searle's attack by "strengthening" the formal system. > This could be done by adding analog states, sensory input/output, etc. > However, if the ultimate criteria for understanding remains a > behavioral one, then skeptical attacks like Searle's cannot be > avoided. Artificial Sentient Beings by the end of the millenium! > 4. Come to a better understanding of the process of understanding, and > different criteria for judging a system than just a purely behavioral one. > I think that the most satisfactory answer to Searle would be "This and > that are what is involved in understanding, and the formal system in > the Chinese room demonstrates (or fails to demonstrate) this and that > here and there." I think that most good AI research is done under this > category, where the emphasis is on understanding how the mind works, > biologically, psychologically, and computationally. Indeed. A sapient system reposes knowledge. An intelligent system thinks and solves problems. A sentient system gathers information from the outside world. A learning system integrates new information into an evolving knowledge base. An ethical system uses that information to effect worthwhile changes to the world in which it is embedded. We have a long way to go. First, artificial intelligence, then artificial sentience, then artificial wisdom. --Barry Kort
bwk@mbunix.mitre.org (Barry W. Kort) (02/28/89)
In article <7645@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) writes: > I merely wanted to illustrate what one of my mathematics > professors once called "proof by intimidation." We should > know better than to invoke such arguments. A few years ago, a poster on this newsgroup introduced the delightful expression "proof by vigorous assertion" for this form of argumentation. It is right up there with another favorite of mine, "invective utterance". --Barry Kort
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (02/28/89)
In article <51123@yale-celray.yale.UUCP> engelson@cs.yale.edu (Sean Engelson) writes: >(Searle + rules) understanding of Chinese? It seems that to >demonstrate or refute the position of understanding being demonstrable >purely through I/O behavior, one must have an effective definition of >understanding. By effective I mean one that does not beg the >question, i.e. by defining understanding to be symbol-processing, or >conversely, to be that which humans do. Sorry, but your constraints are a little weird. Understanding *IS* what humans do. It *MAY* involve symbol processing. What question is begged? What is an effectiver definition? Look how well physicists manage with "force", "charge", "gravity". You cannot ask commentators on humanity for "definitions" that are any less (fast and) loose than those used by commentators on nature. Understanding involves more than lexicography. Let's just define "understanding", no constraints. Stevan Harnad has already pointed to two senses a) the feeling of understanding b) the attribution of understanding. For some domain where something can be right (a) involves thinking that you know what "right" is (b) involves someone else deciding that you know what "right" is (a) is not wholly like pain, but like pain, its perception is a wholly internal event. Where objective tests exist, understanding (a) can only be wrong in the sense of the content of the understanding, as can understanding (b). In both cases, the experience of understanding does not wither away in the face of a failed test. Understanding is monotonic in this sense. Once asserted, the act of assertion is unchangeable, and years after (as we've seen from postings) we can remember just how we felt. (a) is also accompanied by mood changes (elation, nausea etc.). These are probably measurable in some physiological sense. Such measures will be orthogonal to performance on objective behavioural tests. Explain that one. On Searle's room, Searle would not understand Chinese, but neither can the system, since it only "knows" how to understand problems about Chinese and how to output it. There is nothing in (Searle + rules) which asserts "I understand" in response to each problem put to it. The rules just run, and no honest user of the English language would ever attribute understanding to a bunch of rules. As far as more effective computer systems are concerned, it doesn't matter either. The point is one of intellectual honesty, and the distaste felt when groups of supposed academics in a liberal culture fall under the control of a shallow ideology. The question for the strong AI brigade is: "Given the normal usage of understanding, what grounds are there for attributing it to computers, and why bother anyway" While we're at it, what about those halucinogenic thermostats with beliefs. Whatever it was, don't eat it again :-) -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
marty@homxc.UUCP (M.B.BRILLIANT) (02/28/89)
From article <7645@venera.isi.edu>, by smoliar@vaxa.isi.edu (Stephen Smoliar): > In article <230@nbires.nbi.com> matt@nbires.UUCP (Matthew Meighan) writes: >>In article <7586@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) >>writes: >> >>> . . . An argument which is based on assertions >>> of what it "obvious" to introspection is no argument at all >> >>Can you prove this, or is it just obvious to you? >> >>It seems to me that the assertion that only objectively-provable >>things are "true" is a totally subjective one, hence false by its >>own criteria. What evidence is there for this belief? >> > TOUCHE! This is a well-turned argument, forcing me to retreat to reconsider > what it was I REALLY meant! Ultimately, I am trying to get away from using > the word "obvious" too carelessly; but in doing so I seem to have fallen into > the same trap! So how can I get myself out of it? I have a suggestion or two on how to get out of the trap. To begin with, I would suggest avoiding the word "obvious." Whenever a word has different meanings to different people or in different contexts, or otherwise is hard to define, using that word is just asking for trouble. Second, I would suggest falling back to some of the classical ideas of logic, philosophy of science, epistemology, etc. The real basics. There is deductive reasoning and inductive reasoning. You can't prove anything without postulates, because nothing is objectively provable except the subjective fact that you think, therefore you exist, and you can't prove that to anybody but yourself. In the classical paradigm, science treats the objective world primarily in an inductive style. That is, you first make some observations. This is a subjective act. If others can repeat the observations and agree that they are the same, you have, by common consent, an objective fact. Then you think about the observations until you discover a set of postulates which, if processed deductively, would predict the observations. You have just created a theory. You can in fact create several theories to explain the same facts, and then you can use Occam's Razor to choose among them. But Occam's Razor itself is a postulate. So nothing is obvious. You can't agree on conclusions unless you first agree about facts, and then agree on an explanation for the facts. And all the conclusions are tentative. If you want to prove, from a thought-experiment that many people think could never happen, that something that does mere "symbol" manipulation can never "understand" anything, you are opening up a can of worms. In the first place, the observation is not factual. In the second place, the postulates do not lead deductively to an explanation of the presumed facts. If you cannot agree that Searle with a book could fool a native Chinese speaker, you have no facts to explain. If you cannot agree on the definitions of the words, you have no theory to make deductions from. What, please, are the facts? In my humble opinion (IMHO), all we agree on is that we have partial successes, a lot of ambition, and a lot of uncertainty. M. B. Brilliant Marty AT&T-BL HO 3D-520 (201) 949-1858 Home (201) 946-8147 Holmdel, NJ 07733 att!homxc!marty Disclaimer: Opinions stated herein are mine unless and until my employer explicitly claims them; then I lose all rights to them.
harnad@elbereth.rutgers.edu (Stevan Harnad) (02/28/89)
This is a reposting (1st one apparently didn't make it) of a reply to two successive postings by arm@ihlpb.ATT.COM (A. R. Macalalad) of AT&T Bell Laboratories, who wrote: " Now for the sake of argument, let's assume that there is a " distinction between Searle and (Searle + rules)... the only entity able " to decide if (Searle + rules) really understands Chinese is (Searle + " rules). Not you or me or any outside observers or even Searle himself. " Only (Searle + rules). Of course, if we are assuming that much for the sake of argument -- namely, a separate entity that exists and understands -- then of course there is no argument. You've assumed it all. " The issue I now want to take up is your justification of the " Total Turing Test... [tap-dancing, etc.]... The justification for the Total (robotic) Turing Test (TTT) in preference to the Language-In/Language-Out Turing Test (LTT) is fourfold (and has nothing to do with arbitrary calls for tap-dancing): (1) The TTT is what we already use with one another in our everyday, practical "solutions" to the other-minds problem -- not the LTT, which we only use, derivatively, with pen-pals. (2) The TTT (fine-tuned eventually to include neuronal "behavior" too) encompasses all the available empirical data for the mind-modeler. (The only other data are subjective data, and I advocate methodological epiphenomenalism with respect to those.) The LTT, on the other hand, is just an arbitrary subset of the available empirical data. (3) The LTT, consisting of symbols in and symbols out, is open to a systematic ambiguity about whether or not everything that goes on in between could be just symbolic too. (I conjecture that the LTT couldn't be passed by a device that couldn't also pass the TTT, and that a large portion of the requisite underlying function will be nonsymbolic.) (4) Evolution, the symbol grounding problem, and common sense all suggest that robotic (TTT) capacities precede linguistic (LTT) capacities and that the latter are grounded in the former. " Of course, if you'd rather offer an objective definition of... " understanding, please feel free.... As stated many, many times in this discussion, and never confronted or rebutted by anyone, this is not a definitional matter: I know whether or not I understand a language without any need to define anything. " Conduct on the net... I think that a few other apologies are due. I'm trying to criticize views and arguments, not people. If I have offended anyone, I sincerely apologize. (It seems not that long ago that *I* was the one preaching against intemperate and ad hominem postings on the Net as not only ethically reprehensible but an obstacle to the Net's realizing its full Platonic potential as a medium of scholarly communication.) " Being one of those "in the grip of an ideology," I find it remarkably " easy to recognize two systems, and Searle's reply of "internalizing" " the second system only clouds the issue... for true internalization to " take place, the rules must be converted from one system to the other. " In other words, the person has to just sit down and learn Chinese.... One of the tell-tale symptoms of being in the grip of an ideology is that one can no longer tell when one is begging the question... " Let's take a variation of the Chinese room where the purpose of the " room is to interpret [Chinese] BASIC instead of to understand " Chinese... Is it fair to conclude, then, that the system of the person " in the Chinese BASIC room and her bits of paper is not really " interpreting BASIC?... Now who's in the grip of whose ideology? The suspicious reader who might think I stacked the cards by clipping out the ARGUMENTS in pasting together the above excerpt will be surprised to see, upon reading the entire original posting, that there ARE no arguments: The Chinese Room has simply been reformulated in Chinese Basic, and voila! (There's also a double-entendre here on the syntactic vs. the mentalistic meaning of "interpret.") Mere repetition of credos is yet another symptom of ideological grippe. -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/01/89)
[This is a re-posting of a reply that apparently didn't
make it through the mailer.]
dave@cogsci.indiana.edu (David Chalmers) of
Concepts and Cognition, Indiana University writes:
" ["Symbol"] is used [by Searle] to mean two different things:
" (1)... a formal object which corresponds to some HIGH-LEVEL, semantic
" concept in the real world... [e.g.,] a _word_ [and] (2)... any formal
" object... manipulated by a computer program... low-level or
" high-level [or meaningless] [e.g., a neuron]
So far, so good, though I don't find this distinction particularly
useful, because it just concerns how you INTERPRET the meaningless
symbols you're manipulating -- here as words, there as neurons. (In
principle, even the very same program could be interpreted either way.)
But let's go on and see where this leads:
" with sense (1)... I reject the PREMISE of Searle's argument; a formal
" symbol-manipulator could never even display what _looked_ like
" competent Chinese-speaking behaviour
Well, this certainly gives away the store, and I'm inclined to agree.
But I have reasons. Do YOU have better reasons than that you like neurons
better than words?
" [But] Contrary to what Harnad implies, Searle is not only arguing
" against high-level symbol manipulators in the Newell/Simon/Fodor mould.
" He wants to say that NO computer program could... have true
" (subjective) understanding, not even an incredibly complex and subtle
" program (such as a program that simulated a neural network the size of
" the brain.)
Actually, I don't imply otherwise: This is exactly what Searle would
say, because for him it is immaterial how the symbols are interpreted
by the programmer, as words or as neurons: To him they're all just
meaningless symbols. And so are the inputs and outputs (Chinese
symbols, remember? not Chinese neurons). Nor is Searle impressed
with hand-waving about "incredible complexity and subtlety": Symbol
manipulation is just symbol manipulation, no matter how complex the
symbols or the interpretations.
" [Searle] uses the word "symbol" in the low-level sense (2), while
" appealing to our intuitions about symbol-manipulators which manipulate
" high-level symbols of sense (1)!... But AHA - here we have him. These
" low-level (sense 2) symbols... correspond to micro-structural entities
" (such as neurons), which taken alone are devoid of semantics. Semantics
" only emerges when we put enough of these neurons together to form an
" incredibly complex SYSTEM. Despite the fact that the symbols taken
" alone are meaningless, put enough of them together in the right way and
" meaning will be an EMERGENT property of the system, just as it is with
" the human brain.
What we have here is exactly what it sounds like: Not an argument, but
a statement of faith in the "emergent" properties of "incredibly
complex" systems. I feel the same way about clouds sometimes.
The human brain's another story. (The following is almost a paraphrase
of some arguments from my paper, "Minds, Machines and Searle.") Of
course we know the brain "has" semantics. But a symbolic simulation of
a brain is not a brain, any more than a symbolic simulation of a plane
is a plane. Hence there's no reason to believe that a brain simulation
can think any more than a plane simulation can fly.
On the other hand, there is every reason to believe that a correct
brain simulation, like a correct plane simulation, could model
symbolically all of the relevant causal principles we would need to
know about thinking and flying in order to implement their mechanisms
as a brain and a plane, respectively. The implemented brain and plane
could then think and fly, respectively. But they wouldn't be just
symbols anymore either. For one thing, they'd have to have the causal
wherewithal for interacting with the outside world the way brains and
planes do -- and that's not just symbols-in and symbols-out. They would
have to include transducers and effectors (which, as I said before, are
immune to Searle's Argument), and, if the other arguments I've been making
have any validity, it would have to include a lot more nonsymbolic
(analog, A/D, feature-detecting, categorical, D/A) processes in between
the input and the output too.
As long as the system's of the right type, you need make no special
appeal to "incredible" complexity and "emergent" properties (though
it'll no doubt be complex enough). Where you need inordinate amounts of
complexity and equal amounts of credulousness is with a system of the
wrong type, such as a purely symbolic one (or perhaps a purely gaseous
one).
" It is a very mysterious question indeed how real understanding,
" subjective experience and so on could ever emerge from a nice physical
" system like the human brain... nevertheless we know that it does,
" although we don't know how. Similarly, it is a mysterious question how
" subjective experience could arise from a massively complex system of
" paper and rules. But the point is, it is the SAME question, and when we
" answer one we'll probably answer the other.
The first case is certainly a mystery that is thrust upon us by the
facts. The second is only a mystery if we forget that there are no facts
whatsoever to support it, just the massively fanciful overinterpretation of
meaningless symbols.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771harnad@elbereth.rutgers.edu (Stevan Harnad) (03/01/89)
[This is a reposting of a reply that apparently didn't appear the 1st time.] geddis@polya.Stanford.EDU (Donald F. Geddis) of Stanford University writes (in a pair of successive postings): " it might be true that a computer system could not converse " intelligently without being embodied in the real world. But the real " question Searle considered was: How do you determine when a system " is intelligent...? The AI answer is "treat it as a black box and observe " its behavior (have conversations, in this case)". Searle (mistakenly) " disputes this view, and wants us to look inside the system for some " "causal powers"... Just because it requires careful probing and the " examiner can be fooled, doesn't mean that "external behavior" is not " the proper criteri[on] for deciding when a system understands. " Just what, exactly, is being proposed as an alternative test? There are two alternative OBJECTIVE tests for having a mind, the (standard) Linguistic Turing Test [LTT] (symbols-in, symbols-out) and my stronger (robotic) Total Turing Test (TTT) (proximal-projections-of- objects-on-sensors-in, effector-action-on-objects-out). The LTT is a subset of the TTT, but one that is, as I have indicated repeatedly, EQUIVOCAL about the issue of "embodiment" and the putative autonomy of symbolic function from many forms of nonsymbolic function that may be needed in order to pass the LTT in the first place. Searle is only addressing the LTT, and my reply to Searle is that the TTT is immune to his arguments against the LTT. Neither the TTT nor the LTT, however, provides a guarantee that the candidate has a mind. There is and can be no objective test for that, only a first-person subjective one: To perform that, you have to BE the candidate. ONLY this subjective test is decisive. There are two senses in which Searle is advocating "looking inside": One is to look at the functions of the brain, because we have pretty good reason to believe that candidates with brains have minds (because, as I would put it, candidates with brains can pass the TTT). The second sense of "inside" is the first-person test for subjectivity, which we can all perform on ourselves. It's THAT "causal power" that he reminds us brains have but symbol-crunchers do not. My reply is that candidates OTHER than the brain that can pass the TTT (if and when we come up with any) are immune to his Chinese Room Argument that they cannot have a mind (though, of course, I repeat, no objective test can demonstrate that anyone, EVEN ourselves, has a mind). Searle's argument against (hypothetical) candidates that pass the LTT only, with symbols only, is decisive, however. I've always thought this reasoning was quite easy to understand, but from the fact that very few people have given me any objective evidence that they've understood it, I've concluded that it must be difficult to understand. Maybe by trying to put it slightly differently each time, tailoring it to the latest misunderstanding, I'll succeed in making it understood eventually... -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
smoliar@vaxa.isi.edu (Stephen Smoliar) (03/01/89)
In article <125@arcturus.edsdrd.eds.com> gss@edsdrd.eds.com (Gary Schiltz) writes: > >After I started college as an undergraduate in the mid 1970's, I >took my first calculus course. Coming from a small high school in >a small town, my math skills were minimal (a year or so of algebra), >so the whole course was very confusing. In all the time I was in >the course, I never did understand what calculus was all about. >However, I did know, for example, that a derivative was "the equation >you get when you manipulate another equation in such and such a way" >and an integral was "the equation you get when you manipulate the >equation in another way." > >I even had a fair amount of heuristic knowledge about how to solve >word problems. "Hmm, that problem [on the exam] looks like the one >we did in class. Let's see, first you take the derivative >of this and plug in these numbers and solve for this variable, and >then you circle the answer (and even if the answer is wrong, at least >I can get partial credit for showing my work, and if everyone else is >as confused as I am and they don't score well and the exam is graded >on a curve, maybe I can pass)." I seemed to be able to do fairly >good mapping of one problem to another based on its surface structure. > >Well, I did pass the course (now I'm ashamed that I didn't do what >was necessary to understand what was going on, but like a lot of 17 >year olds, I just took the easiest way). I later repeated the course >and understood what I was doing (and made a lot better grade). > >Anyway, from my gut level feeling (quite possibly useless, I admit) >about what understanding is all about, I really feel I had no >understranding of calculus during that semester. Just as the Brazilian >students didn't realize that symbols in physics equations actually >referred to things in the outside world, I didn't know that the >calculus was modelling anything. I truly had no idea that derivatives >had anything to do with rate of change, for example. But, from the >outside, it must have appeared that I had at least some understanding >of calculus; at least I was good enough at manipulating equations to >make the instructors think so. > I find this a very interesting anecdote because it may tell us some interesting things about both introspection and understanding. There is a school of thought which interests me very much and which Marvin Minsky discusses at some length in THE SOCIETY OF MIND which says that when we are trying to solve a problem, we look for a similar problem which we know how to solve and "complete the analogy," so to speak. This seems to be what Gary was doing in his calculus course, and I suspect he is not alone. Indeed, much of my freshman education seemed to be a matter of exposure to problems and their solutions, endowing me with a repertoire I could consult when I had to solve new problems. The first point I wish to make is that neither "looking for a similar problem" nor "completing the analogy" may be as easy to DO as they are to SAY. I think the source of Gary's embarrassment stems from the fact that his similarity metrics were based on what he called "surface structure;" and, indeed, I have encountered some anecdotes from tutoring scenarios which seem to be based on a student dealing with a surface structure "in the wrong way." Now what does that last phrase mean? I suspect what it means is that, to draw an analogy with language processing, we all have some ability to "parse" the "surface structure" of an example of a problem and its solution. However, some of us seem to have the ability to parse it better than others, at least to the extent that we can use the parse tree as a model for solving future problems. Perhaps this metaphor for parsing is what bridges the gap between what we might call "eidetic recall of a solved problem" and what we would call "understanding the solution to a problem." This brings me to my second point. At his "gut level" Gary felt, introspectively, that he really did not understand calculus. Now I know plenty of mathematicians who would claim that you cannot possibly understand calculus until you have been exposed to real analysis. (I had an analysis professor who liked to call his course "advanced calculus done right.") However, let me assume that Gary is an engineer, rather than a mathematician, so that his criterion of understanding has less to do with appreciating the "true" mathematics which underlies all that symbol manipulation and more to do know knowing how to manipulate the symbols in the circumstances of some pragmatic engineering problem. Having let the introspection cat out of the bag, I, for one, would like Gary to attempt to probe further as to just WHY, at that gut level, he felt understanding was eluding him. Did it have to do with problems he could not solve? Did his eyes glaze over whenever he saw integral signs in the pages of a book? Did he just feel that we was struggling more than his fellow students to solve problems? Perhaps if we probe these matters deeper, we may yet return to my initial point: that Gary's "gut level feeling" may leave something to be desired as a criterion for understanding. (One last question to Gary: Can you identify a moment at which you said, "NOW I understand calculus;" and can you recall the circumstances of that moment.)
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/01/89)
In article <Feb.18.17.26.17.1989.23438@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >kck@g.gp.cs.cmu.edu (Karl Kluge) of Carnegie-Mellon University, CS/RI >wrote: >" Ah, but it is a word game... We have Mind A, which we will call John >" Searle, which understands English, and which in its capacity as a >" Universal Turing Machine is emulating Mind B, which we will call Fu >" Bar. Mind A, John Searle, does not understand what is going on in Mind >" B, Fu Bar, whose execution it is simulating. >Ah me. Is it really so difficult to see that in the above you have >simply presupposed the conclusion you were trying to demonstrate? >Before we buy into any dogmas, it is a fact that Searle has a mind, but >definitely NOT a fact that "Fu Bar" has a mind. OK. But Searle is claiming that his lack of understanding shows that Fu Bar (about which both we and Searle know little) does not understand. But that does not follow from Searle's lack of under- standing. For all Searle knows, Fu Bar might understand. I suspect Searle would say that using his brain as a computer (running the program encoded in the instructuions he follows) isn't using his brain in the right way, btu can he prove it? It may have been a mstake to talk about Mind A and Mind B, but I think you are dismissing this point unfairly. That Fu Bar has a mind has not been shown, but neither has it been shown that Fu Bar does not have a mind. So, if nothing is shown, then Searle, who claims to have shown somehting, loses. -- Jeff
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/01/89)
In article <563@aipna.ed.ac.uk> rjc@uk.ac.ed.aipna (Richard Caley) writes: >So it _is_ a definitional problem. Since we have assumed that the >behaviour is identical whether or not it understands, we must rely on >deduction based on the structure of the system to tell us if it >understands. Most significantly, we can't rely on the method we use for >humans - if we ask the room ( presumably in chinese ), it says yes, >otherwise the behaviour is not like that of a native speaker! You haven't said anything that shows it's a definitional problem. I do not see how much can be gained by moving from "does X understand?" to "what does 'understand' mean?" In particular, answers to the second question will not necessarily let us resolve the first. It is always open for someone to say "well, your definition of 'understand' is wrong because there's a counterexample: X isn't doing something that satisfies your definition, but X is understanding." And then we're right back where we started. Or, to look at it another way, what does it matter whether something is called "understanding" or not? What really matters is whether things are the same or different in some interesting way. Think of yourself. If you understand English and do not understand Chinese, do you accept that there's some difference there? Do you have to define "understand" before you can answer, or do you already have an adequate understanding of "understand"? >Without defining understanding we can't argue with it since our >intuitive knowledge of understanding is only for _ourselves_, we apply >it to other people since they seem rater similar, we can _try_ >and apply it to philosophers in rooms or computer systems but I would >not trust the result - Suppose we had the sort of definition you want, and suppose it let us say that X understood and Y didn't. Then someone might say "well, I guess 'understanding' wasn't the right thing to ask about after all." The reason we have problems deciding about computers and philosophers in rooms is that we don't know all that much about how our minds work and because we can never get inside someone else's subjective experience. Definitions of "understanding" do not help with either problem. >Aren't you assuming the result here. If searle running the program is >"-" WRT "understanding" the naturally the system does not understand. You're right here. You're also right that the structure of the system, or something like that, may turn out to be significant. But I think that's about all we can say at this point. After all, we don't have any machines that behave as if able to understand Chinese, so it's hard to say anything about their structural properties. -- Jeff
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/01/89)
In article <Feb.20.21.17.37.1989.16495@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >There is no reason whatever (apart from the preconceptions that >Searle's Argument was formulated to invalidate) (a) not to believe >him or (b) to believe that there is "someone/something" else in the >Chinese Room that IS understanding Chinese in the same sense that >you or I or Searle understand English. It is begging the question to say something else in the room is understanding chinese. But it's not necessary to show that there is something else in order to refute Searle -- all you have to do is show that Searle hasn't shown there isn't something else. Searle does try to show there isn't. Where the "systems argument" goes wrong is by saying "the system understands". But all it really has to do is find a system that Searle hasn't shown to lack understanding. >The difference is that the "external" criteria have not been shown to be >valid, and hence there is simply no justification for taking them to signal >the presence of understanding at all. To merely assume that they do is >not an argument; its just circularity again. Here I more or less agree. The external/behaviorist argument is also reather boring. Well, maybe some people only care about the behavior. That's fine, but some other people may be interested in other aspects too. And the behaviorist approach doesn't address these other issues at all, except to dismiss them.
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/01/89)
In article <4307@cs.Buffalo.EDU> sher@wolf.UUCP (David Sher) writes: >I'd like to hazzard an answer to this question. The reason the AI >establishment tries to answer this question is there is a strong implication >that Searle's argument indicates that symbolic AI approaches will always >lack some performance capability. >Does anyone believe that they can build a machine with a soul? It is >just as easy to build in Searle's "understanding." It's certainly true that it's hard to see what could ever convince Searle that anything had understanding. But I think we can look at a simpler situation and see the kind of thing that might be involved when there's no performance difference. Let's take Chess. At one time, Chess may have seemed a good test of intelligence. But suppose we have two programs, both able to play at the same level. One program constructs strategies and plans. It explicitly represents goals that, if attained, would trap the enemy kind, and so on. The other just uses "brute force" search, but is very fast. It may behave as if it has goals, but it doesn't really have them (in some sense). Both of these programs are just doing symbol manipulation, and both can play at the same level; but we can still see that they work in different ways. Indeed, the second program is more "mechanical". Both programs can be seen as using only simple, low-level operations; but the first program can also be analyzed in terms of goals and plans while (let us suppose) the second one cannot. That is, the structure of the program doesn't show that kind of organization -- it's behavior is another matter. So I think we can imagine cases where there is no performance difference but where there are other interesting differences we can discover. -- Jeff
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/01/89)
In article <573@aipna.ed.ac.uk> rjc@uk.ac.ed.aipna (Richard Caley) writes: >(b) is, surely, a straw man. It is the homoculous argument again. Nobody >is claiming there is "something else" in the room which understands >chinese. Nope. Imagine that some part of Searle's brain is running the Searle program and another part is running the Chinese Room program. No infinite regress, just time sharing.
dave@cogsci.indiana.edu (David Chalmers) (03/01/89)
harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >dave@cogsci.indiana.edu (David Chalmers) writes: > >" with sense (1) [the high-level sense of "symbol"]... I reject the >" PREMISE of Searle's argument; a formal symbol-manipulator could never >" even display what _looked_ like competent Chinese-speaking behaviour. > >Well, this certainly gives away the store, and I'm inclined to agree. >But I have reasons. Do YOU have better reasons than that you like neurons >better than words? Certainly I have reasons. Have you got a couple of hours? I didn't think this was the time or the place for a switch of topic to an issue far more complex than Searle's misleading intuition pump. > >" [Searle] uses the word "symbol" in the low-level sense (2), while >" appealing to our intuitions about symbol-manipulators which manipulate >" high-level symbols of sense (1)!... But AHA - here we have him. These >" low-level (sense 2) symbols... correspond to micro-structural entities >" (such as neurons), which taken alone are devoid of semantics. Semantics >" only emerges when we put enough of these neurons together to form an >" incredibly complex SYSTEM. Despite the fact that the symbols taken >" alone are meaningless, put enough of them together in the right way and >" meaning will be an EMERGENT property of the system, just as it is with >" the human brain. > >What we have here is exactly what it sounds like: Not an argument, but >a statement of faith in the "emergent" properties of "incredibly >complex" systems. I feel the same way about clouds sometimes. > Answer me these questions. (1) Do you believe neurons (taken alone) have semantics. [I take it the answer has to be "No."] (2) Do you believe the brain as a whole has semantics. [I take it the answer is "Yes."] Given this, you must accept that semantics can arise out of non-semantic objects. Most of us are a little baffled as to how. It seems that the only half-way reasonable tack we can take to answer this question is to say that what is important for semantics (and the subjective in general) is not so much those objects as the complex patterns that they form. After all, neurons taken alone are pretty simple entities which can't carry much in the way of information. As is well known, information is carried by complexity (and the greater the complexity, the greater the information which can be carried). It seems to me that "information" and "semantics" are very closely related concepts. The fact that complexity is a necessary condition for information would suggest that appeals to complexity are not mere hand-waving. >[A correct brain simulation would] have to have the causal >wherewithal for interacting with the outside world the way brains and >planes do -- and that's not just symbols-in and symbols-out. They would >have to include transducers and effectors (which, as I said before, are >immune to Searle's Argument), and, if the other arguments I've been making >have any validity, it would have to include a lot more nonsymbolic >(analog, A/D, feature-detecting, categorical, D/A) processes in between >the input and the output too. This strikes me as rather like the point-missing "Robot Reply" in Searle, despite your disclaimers. I thought that the "Stephen Hawking argument" was a rather good reply to this stuff. What's important for subjective experience is a brain state, not a bodily state; and AI claims to be able to simulate any brain state whatsoever (just give it time). So Searle's arguments still would apply. You could paralyze me and put me in a sensory deprivation tank, but still (for some time at least) I would have subjective experience. >" It is a very mysterious question indeed how real understanding, >" subjective experience and so on could ever emerge from a nice physical >" system like the human brain... nevertheless we know that it does, >" although we don't know how. Similarly, it is a mysterious question how >" subjective experience could arise from a massively complex system of >" paper and rules. But the point is, it is the SAME question, and when we >" answer one we'll probably answer the other. > >The first case is certainly a mystery that is thrust upon us by the >facts. The second is only a mystery if we forget that there are no facts >whatsoever to support it, just the massively fanciful overinterpretation of >meaningless symbols. > And presumably, if we were all made of paper we'd say the same thing. "It's easier and safer to assume that neuro-thingies don't support TRUE experience; and after all we have no direct evidence for it, only their meaningless claims. So lets just ignore anything which these systems have in common (viz. extreme complexity, intelligent behaviour) and just concentrate on their differences." I don't want to be inflammatory, but it sounds not unlike many an argument used by a racist in days gone by. Dave Chalmers Center for Research on Concepts and Cognition Indiana University
bwk@mbunix.mitre.org (Barry W. Kort) (03/01/89)
In article <Feb.26.15.55.22.1989.7914@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) laments about the difficulty of explaining his ideas about the Total Turing Test: > I've always thought this reasoning was quite easy to understand, but from > the fact that very few people have given me any objective evidence that > they've understood it, I've concluded that it must be difficult to > understand. Maybe by trying to put it slightly differently each time, > tailoring it to the latest misunderstanding, I'll succeed in making it > understood eventually... Stevan, would it help if I confessed that I was most captivated by the sample dialogues found in Turing's paper, and later exemplified in Hofstadter's Pulitzer Prize winning book? I know that a lot of technical specialists look down upon such frivolous and fanciful dialogues, but if the goal is to successfully communicate an idea, it helps to dramatize the material. For some reason, people love a good story with some emotional give and take. --Barry Kort
hansw@cs.vu.nl (Hans Weigand) (03/01/89)
In article <Feb.23.22.02...> harnad@elbereth.rutgers.edu (Stevan Harnad) wrote: >lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii wrote: > >" No, there aren't "two senses of "understand," a subjective and an >" objective one," [otherwise we couldn't say] 'He understands, and I do too' > >As I've suggested already, this is simply not a linguistic matter. ... >[there] is both an objective and a subjective sense of understanding. > Can't we reconcile these two standpoints by saying that "understanding" has only one "sense" (linguistic meaning), but that this sense has two aspects (facets), objective and subjective? Cognitive scientists and philosphers must distinguish between objective and subjective aspects of intentional attitudes, but they must also be careful not to abolutize these aspects, because this easily leads to abstractions prone to paradoxes. For the rest, I agree with Stevan. Hans Weigand, Dept of Mathematics and Computer Science Free University, Amsterdam
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (03/01/89)
In article <9739@ihlpb.ATT.COM> arm@ihlpb.UUCP (55528-Macalalad,A.R.) writes: >here and there." I think that most good AI research is done under this >category, where the emphasis is on understanding how the mind works, >biologically, psychologically, and computationally. Ahem. You've missed out the social aspect of mind. A while back, Don Norman re-iterated the fact that all interesting performance judgements are social judgements. Unfortunately, some Waldenite from USCD later came back with the nonsense that intelligent arises from ONE individual interacting with the physical environment. Remind me not to go to any of his parties :-) :-) The facts, for the most die-hard positivist, are that without proper early socialisation, children end up worse than animals (how many times do I have to say this?) Whilst the Walden dream of one man, his biology, psychology and (presumed) computations may appeal to many Americans, remember that this ideal is nothing more than a fiction, though a profoundly appealing one to many in the new world. Yes, we do work out problems on our own, but only as a result of interactions with others. One cannot work from the individual to society, from one intelligent agent to a co-operating community with a living, viable culture. Society is not the individual writ large (all though some political ideologies do hold this). (As for the Mad Ox of Cyperpunk - have the decency not to take any of the content here as xenphobia. I have a number of American friends and have a balanced view of your marvellous country, but American individualism isn't a science). -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (03/01/89)
In article <7645@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) writes: Thus, I would argue that the manifestation of intelligent >behavior cannot be observed the way we observe the size of a physical object. GOTCHA! OK Stephen, so what are the implications for this of a science of Mind? -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
bwk@mbunix.mitre.org (Barry W. Kort) (03/01/89)
Now that I think about it, I, too, took a course in which I failed to comprehend the subject, yet I could mechanically do the motions which, on the surface, suggested I knew what I was doing. The course was a compressed introduction to Probability and Statistics for people who had completed their undergraduate curriculum but hadn't yet entered grad school. We met 5 days a week for 2 months. It was brutal. At one point, the professor introduced the notion of Borel Sets, which provide an abstract foundation for probability theory. Now Borel sets are unreal, like fractal dust. Very hard to understand. There were a series of theorems and proofs that no one understood. But for some peculiar reason, the proofs always started out with "Pick a partition...". Now none of us knew what the professor meant by "pick a partition". But by the time he got to the fourth proof, he said, "How do we prove this?". The class answered in unision, "Pick a partition." "RIght," he said, and proceeded to complete the details of the proof. Twenty years later, I still don't know what he meant. --Barry Kort
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (03/01/89)
From article <Feb.23.22.02.54.1989.5138@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): " " lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii wrote: " "" No, there aren't "two senses of "understand," a subjective and an "" objective one," [otherwise we couldn't say] 'He understands, and I do too' This is, I take it, a tangential point. I had said that Searle's argument showed no essential difference between computers and people and turned on a mere point of usage of the term 'understanding'. Then I went on to say that *even* the point about usage was not very well taken, as one can see easily enough once one recognizes the terminological nature of the argument. Now it's this secondary question of usage that is being discussed, as far as I can make out. Harnad says there's a "true" sense of 'understand' with respect to which we should agree with Searle's terminological argument. Maybe so. I don't think so, but even if I'm wrong, and Searle has done some first rate linguistics here, the main point seems to have been established. There is no substance to the Chinese Room argument -- it's just toying with words. " As I've suggested already, this is simply not a linguistic matter. I noticed that suggestion. But then you keep citing (purported) facts about language usage and giving linguistic analyses to support your views. At least, if the analyses you give are intended to have any empirical content, I don't see how else they can be construed. When you propose this distinction of yours between understanding(subjective) and understanding(objective), how are we to take this? Are you making a definition for convenience of discussion? If so, fine. You can make any definitions you want. Or maybe you're declaring that as a matter of personal taste, you like to make this distinction. Well, to each his own. The trouble is, you seem to think you're doing more -- that there really *is* a distinction of the sort you claim, and that it's a matter to which some sort of factual evidence is relevant. And the only evidence you offer concerns language usage, so when you say it's "simply not a linguistic matter", how can we believe you? You're simply wrong. As you have put the issue so far, it *is* a linguistic matter. If the existence of this distinction you claim is not intended to be an empirical proposal, then it's time for you to say so. In that event, I will have no further interest, personally. If it is intended to be empirical, and facts other than those of language usage can be found to suppport it, then it's time for you to say what those facts are. Until then, I guess we'll continue to talk linguistics. " The distinction I'm after is already there with "pain" (although we don't " have two senses of pain as we do of understanding -- the reason for " this will become clearer as we go on). Consider "I'm in pain and he is " too." Apart from the obvious fact that I don't mean he's in MY pain " (which is already a difference, and not a "linguistic" one but an " experiential and conceptual one), I'll comment on the parenthetical. There are several interesting things about this construction, but they are susceptible to linguistic analysis, and they have nothing to do with 'pain' being "experiential". In 'He is in (his) pain', the "his" part is understood, but cannot be made explicit. Similarly, 'He is red in the (his) face'. Is it because pain and faces are subjective? Nope. It has to do with inalienable possession. A face is linguistically an intrinsic inseparable part of a person (for English). Many languages of the world make a distinction between alienable and inalienable possession. It turns up in different forms. It's complicated. It's linguistic. Another interesting thing about your example is the sloppy identity between the 'in (my) pain' antecedent and the elided 'in (his) pain'. The phenomenon has received lots of discussion since Haj Ross talked about it in his 1967 dissertation. Compare 'Mary said that she'd like to have her steak rare, and John did, too' -- which has as one possible interpretation '... John said he'd like to have his steak rare, too'. Let's see -- is this because steaks, or saying or liking are inherently subjective phenomena? Nope. Missed the boat again. It's a question of syntactic scope. " it makes sense to say "He SEEMS to be " in pain (but may not really be in pain)," but surely not that "I SEEM " to be in pain (but may not really be in pain)." On the contrary. 'I seem to be in pain' is a perfectly ordinary thing to say. 'Hey, Doc, I've been taking these pills for weeks now, and I still seem to be in pain.' But maybe you disagree with this. If so, can we take a survey to settle the matter? Or, if most people agree with me, will you say "Oh, you're just not using 'seem' *properly*." Or maybe we'll have a distinction between seem(subjective) and seem(objective). " (Please don't reply " about tissue damage, ... Wouldn't think of it. " ... "" Pardon me if I implied that only philosophers do second-rate linguistics. " " I won't make the obvious repartee, but will just repeat that these are not " linguistic matters... I shouldn't have been snide. I'm sure you could do some very good linguistics IF YOU KNEW YOU WERE DOING IT. Offering facts of language and linguistic analyses without understanding that you're actually doing linguistics is a big handicap. " [In a later posting Lee mixes up the syntax " of the (putative) symbolic "language of thought" -- whose existence and " nature is what is at issue here -- and the syntax of natural languages: " Not the same issue, Greg.] I haven't the foggiest idea of what mixing up you are referring to. I'm reasonably sure I never said anything about a "language of thought". What are you talking about? Greg, lee@uhccux.uhcc.hawaii.edu
ins_atge@jhunix.HCF.JHU.EDU (Thomas G Edwards) (03/02/89)
In article <45199@linus.UUCP> bwk@mbunix.mitre.org (Barry Kort) writes: >Recall the breakthrough scene in the Helen Keller Story. ... >The Chinese Room is like Helen before her moment of epiphany. >There is little point in manipulating symbols mechanistically >unless one can map the symbols to non-symbolic sensory >information from the external world. It is certainly true to assume that sensory perceptions from "the enviroment" (outside the cognitive device) are neccesary for real-world reasoning. (Galileo pointed that out in _Dialogue Concerning the Two Chief World Systems_, although he was only talking about human brains). Internal rules are not enough. However, in the Chinese Room experiment, we are assuming that the rule operator has indeed been endowed with rules to operate on, and as such these rules are defacto sensory input from the outside. Moreover, the incomming Chinese is also sensory input. Rules may exist which change due to incomming Chinese. Furthermore, what are these rules? Do these rules include sensory information (i.e. is there a rule which deals with what-is-trees which includes a picture of a tree)??? One more angle on this entire situation is that neural-networks can often be described by symbollic rules. Often discovering these rules from learned weights can be difficult, but there have been some breakthroughs (i.e. shading --> concave or convex object? Sejnowski has taught a NN to do the shading to concave or convex and determined symbolic rules). I feel though that NN's give symbollic rules a richer "spectrum", and that it's much easier to induce new nerual weights than to induce new symbollic rules. Even if you are still not quite convinced that NN's can be reprsented by symbollic rules, take every neuron to be a rule which takes the weighted sum of activations of rules connected to it and perform a function on the rule activation, and propogate that along directed edges to other rules... -Thomas Edwards ins_atge@jhuvms bitnet
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/02/89)
dave@cogsci.indiana.edu (David Chalmers) of Concepts and Cognition, Indiana University wrote: " [Concerning symbolic modeling vs neural modeling] I didn't think this " was the time or the place for a switch of topic to an issue far more " complex than Searle's misleading intuition pump. No switch. That IS Searle's topic. It is most respondents who have over-simplified it. " Do you believe neurons (taken alone) have semantics[?] [I take it the " answer has to be "No."] Do you believe the brain as a whole has " semantics[?] [I take it the answer is "Yes."] Given this, you must " accept that semantics can arise out of non-semantic objects... " not so much those objects as the complex patterns that they form. Of course semantics arises out of nonsemantic objects. But there are nonsemantic objects and nonsemantic objects -- and scratches on paper (even when implemented as symbol-crunching computer programs) do not seem to be the right kinds of objects. Likewise there are patterns and patterns. My "Robotic Functionalism" IS a form of functionalism -- it does hold that cognitive function is some "pattern" of physical function. But, unlike standard "Symbolic Functionalism," it denies that that pattern of physical function consists merely of formal symbol manipulation. It can be SIMULATED by symbol manipulation; but if what is simulated is not merely symbolic function (e.g., if an essential part is analog processing) then it cannot be IMPLEMENTED as just symbol manipulation. (And, as I said in my postings and article: Only implemented planes/brains can fly/understand.) " The fact that complexity is a necessary condition for information would " suggest that appeals to complexity are not mere hand-waving. But necessary conditions are not sufficient conditions. And mere complexity will not you a mind get. There's complexity and complexity; and a lot more conceptual work to do before you have a viable model for the mind. " [Harnad's "Robotic Functionalist Reply"] strikes me as rather like the " point-missing "Robot Reply" in Searle, despite your disclaimers. I " thought that the "Stephen Hawking argument" was a rather good reply to " this stuff. What's important for subjective experience is a brain " state, not a bodily state; and AI claims to be able to simulate any " brain state whatsoever According to Robotic Functionalism, the device -- the "inner core," the "brain-in-a-vat," or whatever you like -- that will be able to successfully pass the Linguistic version of the Turing Test (LTT) (symbols-in, symbols-out) will have to have and draw upon the internal causal wherewithal to pass the Total (robotic) Turing Test as well (even if it does not have to display it behaviorally). I'm sure Stephen Hawking has that inner core; and it's just a current blinkered fantasy that that inner core consists of nothing but a symbol-cruncher! Hawking's intact internal nonsymbolic (brain) functions are crucial to his having a mind whether or not he can or does display them in any other form than a verbal one. (Or didn't people in AI know that if you yanked off from the brain the "body" and all its sense organs -- some of which happen to be PART of the brain, by the way -- you weren't just left with a digital computer?) " if we were all made of paper we'd say the same thing: "It's easier and " safer to assume that neuro-thingies don't support TRUE experience; and " after all we have no direct evidence for it, only their meaningless " claims. So lets just ignore anything which these systems have in " common (viz. extreme complexity, intelligent behaviour) and just " concentrate on their differences."... I don't want to be inflammatory, " but it sounds not unlike many an argument used by a racist in days gone by. And if my grandmother had wheels, or the world were one-dimensional, or stones had minds... You can't make a counterfactual and implausible conclusion seem more plausible by simply adopting it as a premise. Ref: Harnad (1989) Minds, Machines and Searle. Journal of Experimental and Theoretical Artificial Intelligence" 1: 5-25 -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
sher@sunybcs.uucp (David Sher) (03/02/89)
Just to test out what is and isn't a symbolic system. Consider a
stochastic context free grammar. This is a grammar that has
a probability associated with each production. Thus each element of the
language it accepts has a probability associated with it (along with
a certain probability that the machine never outputs anything).
Now consider a machine that takes a stochastic grammar and an input string
and outputs the most probable parse tree for the input. Is this machine
doing symbolic processing? Or is more information required to answer this
question. Assume it used a modified form of Earley's algorithm to do
this. Now is it doing symbolic processing?
If enough people are interested in how to modify Earley's algorithm to
accept stochastic grammars I can post (or even write a paper on the topic
if it hasn't been done yet). Its fairly trivial.
-David Sher
ARPA: sher@cs.buffalo.edu BITNET: sher@sunybcs
UUCP: {rutgers,ames,boulder,decvax}!sunybcs!sherjgn@nvuxr.UUCP (Joe Niederberger) (03/02/89)
In article <17923@iuvax.cs.indiana.edu> dave@duckie.cogsci.indiana.edu (David Chalmers) writes: <lots of good stuff deleted> >It is a very mysterious question indeed how real understanding, subjective >experience and so on could ever emerge from a nice physical system like >the human brain, which is just toddling along obeying the laws of physics. >But nevertheless we know that it does, although we don't know how. >one. Just remember, semantics CAN arise from syntax, as long as the >syntactical system is complex enough, and involves manipulating >micro-structural objects which interact in rich and subtle ways. Now, I am not religiously convinced either of the truth or falsity of the above statement, but I can't help noticing the fervor implied by the capitalized "CAN." But isn't it the point of this discussion to present evidence supporting or contradicting a held belief? If I were to grant that David's argument against Searle's "proof" was valid, I may still be unmoved (and logically uncompelled) to agree with his claim that semantics CAN arise from syntax. If the reference to the human brain is the evidence he offers, I ask: why must I view the brain as a syntactical system ? Yes, it may be an interesting hypothesis that the brain's essential function is to serve as a syntactical system, (and this may deserve further investigation,) but lack of a disproof doesn't serve as a proof for me. Joe Niederberger
sarima@gryphon.COM (Stan Friesen) (03/02/89)
In article <4307@cs.Buffalo.EDU> sher@wolf.UUCP (David Sher) writes: > >I probably blew it, being far from an expert in rhetoric, but this seems >to be the nub of the problem. Does anyone believe that they can build a >machine with a soul? It is just as easy to build in Searle's "understanding." > Yes, I do. Of course this is at least partly because the Jewish rather than the Greek definition of soul! By the way, I also believe that the Chinese Room as specified by Serle is impossible. I do not beleive that a fully native competence in a language may be achieved by pure symbol manipulation using predefined rules. A certain amount of world knowledge and "common sense" must also be applied. I base this in part on my experience translating technical Russian using only a dictionary and a skeleton grammar. I could not have done it without "understanding" the Russian as I went, thus I would have been at a loss trying to translate a book on something I did not know anything about. -- Sarima Cardolandion sarima@gryphon.CTS.COM aka Stanley Friesen rutgers!marque!gryphon!sarima Sherman Oaks, CA
dave@cogsci.indiana.edu (David Chalmers) (03/02/89)
harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >Of course semantics arises out of nonsemantic objects. But there are >nonsemantic objects and nonsemantic objects -- and scratches on paper >(even when implemented as symbol-crunching computer programs) do not >seem to be the right kinds of objects. I think I'll just let this 'argument' stand as it is, displayed in all its glory. > Likewise there are patterns and patterns. "A pattern is a pattern is a pattern" - G. Stein. So: we both agree... meaningless NEURONS are related in COMPLEX ways to form representational PATTERNS which support a mind but meaningless SYMBOLS are related in COMPLEX ways to form representational PATTERNS which...? I leave the reader to draw her own conclusion. >[On complexity supporting information.] >But necessary conditions are not sufficient conditions. And mere >complexity will not you a mind get. There's complexity and complexity; >and a lot more conceptual work to do before you have a viable model >for the mind. Indeed you're right, and I don't expect this problem to be solved overnight. But see my forthcoming "Mind, Pattern and Information" (tentatively retitled "The First-Person and the Third-Person: A Reconciliation"). Not all complexity supports information, and not all complexity supports a mind either. But at the bottom line the criterion lies in the _structure_ of the complex system and not in the raw materials. Dave Chalmers Center for Research on Concepts and Cognition Indiana University
dave@cogsci.indiana.edu (David Chalmers) (03/02/89)
jgn@nvuxr.UUCP (22115-Joe Niederberger) writes: >dave@duckie.cogsci.indiana.edu (David Chalmers) writes: >>[...] Just remember, semantics CAN arise from syntax, as long as the >>syntactical system is complex enough, and involves manipulating >>micro-structural objects which interact in rich and subtle ways. > >Now, I am not religiously convinced either of the truth or falsity of >the above statement, but I can't help noticing the fervor implied by the >capitalized "CAN." [...] I may still be unmoved (and logically uncompelled) >to agree with his claim that semantics CAN arise from syntax. If the >reference to the human brain is the evidence he offers, I ask: why >must I view the brain as a syntactical system ? Apologies for religious fervour. The capitalization was in response to Searle's repeated claim that "syntax cannot arise from semantics." Searle uses this premise repeatedly to support his argument. When Searle talks of "syntax", he is not referring to the usual linguistic usage of the term. He applies it to mean "any system of meaningless objects whose behaviour is determined by formal rules" (or something like that), because this is the meaning he needs to support his argument. But once we see that this is the meaning he is using, we can simply point to the human brain: Meaningless objects (neurons etc) are obeying formal rules (the laws of physics), and yet semantics is indisputably arising. Counterexample - so game, set and match to the good guys. >Yes, it may be an interesting hypothesis that the brain's essential >function is to serve as a syntactical system, (and this may deserve >further investigation,) but lack of a disproof doesn't serve as a >proof for me. I think you probably mean "syntactical" in the linguistic sense here, which is a sense which neither Searle nor I intended. But your interpretation is a very natural one, and I believe that this is again indicative of the misleading way with which Searle plays with our intuitions. When he says "syntax", our immediate image is of linguistic objects (those high-level sense-(1) symbols, remember?), and of course in this case syntax is not sufficient for semantics: using sense (1) symbols syntactically leaves out the most important part, their meaning. But these intuitions do not apply to the low-level syntax of sense (2) symbols (which, of course, never had any meaning to begin with - their meaning lies in the systems they form). Incidentally, the hypothesis that the function of the brain is to serve as a syntactical system (in the high-level linguistic sense) is a central tenet of many in the "Symbolic" school of AI. (In particular it is quite explicitly the backbone of Fodor's thinking - see his "The Language of Thought", if the title doesn't say it all.) Needless to say, this is a hypothesis with which I strongly disagree. Dave Chalmers (dave@cogsci.indiana.edu) Center for Research on Concepts and Cognition Indiana University
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/02/89)
lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii wrote: " Harnad says there's a "true" sense of 'understand' with " respect to which we should agree with Searle's terminological " argument. Maybe so. I don't think so, but even if I'm wrong, " and Searle has done some first rate linguistics here, the main " point seems to have been established. There is no substance to " the Chinese Room argument -- it's just toying with words. It's amazing to me how trapped people can be in their preconceptions. IF Searle's is just a terminological point THEN he is indeed just toying with words. But if there exists a real experience, called understanding (vs. not understanding) a language, an experience we all have, and know perfectly well that we have, and can perfectly well recognize when we do and don't have, then Searle's is by no means just a terminological point or word-play, and he is not doing any kind of lingustics here, first-rate or otherwise. Now I keep trying to remind people (who have managed to forget or not notice) that this simple, familiar, sufficiently unambiguous EXPERIENCE of understanding is the only thing whose presence or absence is at issue in the Chinese Room Argument. Forget about terminology. Call it whatever you like. Searle's saying he has it with English and not Chinese. This is no more a linguistic matter than "My left side aches and my right side doesn't"! " you keep citing (purported) facts about language usage and giving " linguistic analyses to support your views. At least, if the analyses " you give are intended to have any empirical content, I don't see how " else they can be construed. If I remind you what you mean be "My left side aches and my right side doesn't," I am not giving a "linguistic analysis." I can't avoid that a verbal discussion should be in words, but we are not discussing words, we're discussing their referents, and in this case these are subjective experiences. Facts about subjective experience are empirical too. " When you propose this distinction of yours between understanding " (subjective) and understanding (objective), how are we to take this?... " you seem to think... there really *is* a distinction of the sort you " claim, and that it's a matter to which some sort of factual evidence is " relevant. And the only evidence you offer concerns language usage, so " when you say it's "simply not a linguistic matter", how can we believe " you? You're simply wrong. It's a peculiar feature of coherent, substantive distinctions that "there really *is* a distinction" there. In this case it's between two "things," both called by the name "understanding." One of them is the experience that we were discussing: Those of us who have not bought into a contemporary ideology (and the rest of us before they bought into the ideology) knew perfectly well what it was like to understand or not understand a language, from the first-person standpoint. That's (subjective) understanding. We also distinguished objective features that tended to accompany this subjective understanding, in ourselves and in others too, and we called that understanding (objective) too: I know what it's like to (subjectively) understand English (and so do you). And he speaks and acts AS IF he (objectively) understands English. The empirical evidence for the existence of the former is our 1st-person subjective sense of what it's like to understand English. The empirical evidence for the existence of the latter is the objective verbal and behavioral data that tend to accompany the former and that we take to constitute expressions of objective understanding. I could do exactly the same (nonlinguistic) number on the distinction between pain and tissue damage, or, for that matter, the distinction between a left- and a right-sided ache. " If [the distinction] is intended to be empirical, and facts other than " those of language usage can be found to suppport it, then it's time for " you to say what those facts are. Until then, I guess we'll continue to " talk linguistics. See above. (Or perhaps I should say "look at" the above, for I can only make you do the objective thing, not the subjective one. -- I am, by the way, striving for an OBJECTIVE understanding of the points I'm making on your part, not just the subjective sense of it...) " There are several interesting things about... "I'm in pain and he is " too" but they are susceptible to linguistic analysis, and they have " nothing to do with 'pain' being "experiential"... The several things you go on to mention (about Mary, and her steak, and syntactic scope) may indeed be interesting, and they certainly are linguistic, but they are not RELEVANT, because, as I have been suggesting to no avail: This is not a syntactic matter! And the relevant part has everything to do with pain being experiential. " 'I seem to be in pain' is a perfectly ordinary thing to say... " can we take a survey to settle the matter? Do you really think that the deep issues involved in the problem of the incorrigibility of subjective experience reduce to a question about an idiom, about which we can take a survey? Maybe if I spell it out for you: "It is true that it feels as if I have a splitting headache right now, but then maybe it's not true that it feels as if I have a splitting headache right now." THAT's what's at issue when I say "I only SEEM [stress] to be in pain." (Does the "only" plus the stress on the "seem" help dispel the inclination to resort to your idiom again?) And I repeat: I'm not doing a linguistic analysis here. I'm talking about the "empirical evidence" for pain: It comes in an incorrigible subjective package. The word-play seems to be [sic] on your end; but mostly what you are doing is begging the question and changing the subject (to linguistics). " I haven't the foggiest idea of what mixing up you are referring to... " [in the claim that in a later posting Lee mixes up the syntax of the " (putative) symbolic "language of thought" -- whose existence and nature " is what is at issue here -- and the syntax of natural languages] I'm " reasonably sure I never said anything about a "language of thought". " What are you talking about? Searle's Argument is about whether thinking is just formal symbol-manipulation in the (purely syntactic) "language of thought." In another posting, as in this one, you digressed into irrelevant matters concerning English syntax. One way to make a self-fulfilling prophecy of the claim that Searle's Argument is just linguistic is to treat it only as linguistic. Well you could have gone further, ignoring its content completely, and only correcting his grammar... -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
jps@cat.cmu.edu (James Salsman) (03/02/89)
And another thing for all you neural soup floating-point numerical dweebs that think a symbol system can't **EVEN APPROXIMATE** competence in language: It wouldn't be that hard to write Eliza for Chinese, and you could even train a human to manually execute the code! :James -- :James P. Salsman (jps@CAT.CMU.EDU) --
matt@nbires.nbi.com (Matthew Meighan) (03/03/89)
dave@cogsci.indiana.edu (David Chalmers) of
Concepts and Cognition, Indiana University writes:
" It is a very mysterious question indeed how real understanding,
" subjective experience and so on could ever emerge from a nice physical
" system like the human brain... nevertheless we know that it does,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
" although we don't know how. Similarly, it is a mysterious question how
" subjective experience could arise from a massively complex system of
" paper and rules. But the point is, it is the SAME question, and when we
" answer one we'll probably answer the other.
This 'we know that it does' seems, to me, to be a remarkable assertion.
I don't see how any such thing has been (or ever can be) shown, and would be
interested to hear an objective proof of this.
If you want to say "nevertheless I like to assume that it does", that's fine.
My own view is that subjective experience does not arise from the
brain at all, but vice versa -- that the brain, and the rest of the
physical body, is evolved by consciousness to give itself a vehicle
with which to interact with other consiousnesses. Understanding
and subjective experience do not exist in the brain at all, but in the
mind, of which the brain is just the most obvious and least-subtle part.
This viewpoint is plainly not provable -- that is, I can't prove it to
YOU from MY experience. For me, it is both 'subjectively' true because
it is what I feel, and 'objectively' true because I have observed
phenomena I can't explain any other way. Those phenomena are
scientific evidence to me, because I know they took place, and I would
have to ignore the data to conclude other than I have. But they
would be mere heresay to you, hence no evidence at all.
My real point, though, is that your view that consciousness "arises"
from the physical brain is as purely subjective as mine that it is the
other way around. It seems to me that this assertion is a leap of
faith, resembling more a religious conviction than a scientific one.
You might be right, though, that the two questions you pose are the
same one, and that the answer to one answers the other. It is
self-evident to me (though not necessarily, of course, to anyone else)
that the answer to both questions is "It doesn't." Perhaps (in what I
think is the reverse of the sense in which you said that if we answer
one question we can answer the other) we should take the fact that
understanding does NOT emerge in computer programs as evidence that it
does NOT emerge in brains, either.
One could agrue (and some have) that understanding MAY arise in some
computer program someday, that the ones we have are just not complex
enough. But then we are really drifting from the facts into pure
speculation, aren't we? It can be said of anything that it may happen
someday; the data we have at this point is that this has never happened.
I see no reason to assume that a *quantative* 'increase in complexity'
will automatically cause a qualitative change of the magnitude of
"the emergence of consciousness"; until such a thing takes place there
is no reason to suppose it will. The more likely outcome is that as
we make programs more complex, we will have exactly the same
qualitatively stupid things we have now -- just more complicated ones.
The questions of what constitutes understanding, or intelligence, are
intrinsically interesting and important ones. But I am not sure that
they are very important to AI. All we have to do is create machines
that APPEAR to be intelligent (challenge enough!). We seem to be
debating the question "Can we make machines that actually understand,
in the sense that we do?" As a human being, my answer tends to be "of
course not!". But as a programmer, I would more likely respond "What
difference does it make?"
--
Matt Meighan
matt@nbires.nbi.com (nbires\!matt)bwk@mbunix.mitre.org (Barry W. Kort) (03/03/89)
In article <917@jhunix.HCF.JHU.EDU> ins_atge@jhunix.UUCP (Thomas G Edwards) writes: > However, in the Chinese Room experiment, we are assuming that > the rule operator has indeed been endowed with rules to operate > on, and as such these rules are defacto sensory input from the > outside. > Moreover, the incomming Chinese is also sensory input. > Rules may exist which change due to incoming Chinese. Perhaps Stevan can clarify this point for us, because I believe it is pivotal. In Searle's thought experiment, are the rules immutable, or do they evolve as a function of the information contained in the Chinese stories? As I recall, Searle set it up so that the rules didn't change as a function of the Chinese input. To my mind, a system which understands is a system which integrates new information into an expanding knowledge base, and this includes new and improved information-processing techniques (i.e., the "rules"). When we talk about "understanding" in human terms, don't we really mean the ability to gain understanding (as opposed to merely having a fixed amount of understanding)? --Barry Kort
arm@ihlpb.ATT.COM (Macalalad) (03/03/89)
In article <Feb.28.10.58.44.1989.18905@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >As stated many, many times in this discussion, and never confronted >or rebutted by anyone, this is not a definitional matter: I know >whether or not I understand a language without any need to define >anything. Stevan, no one is disputing whether or not you know whether you understand a language, least of all me. Maybe my argument wasn't too clear, so let me try to clarity things. Argument: In order to come to any resolution about what systems can or cannot understand, we need an objective theory of understanding, rather than the behaviorist "I'll know it when I see it" tests such as the Linguistic Turing Test (LTT) or the Total Turing Test (TTT). Now you may be totally confident that you know when you understand a language, but to conclude that you know when another entity understands a language is a leap that I'm not quite ready to make. The problem I have, of course, is the Other Minds Problem, which roughly stated is the problem of knowing for certain whether other entities understand/comprehend/are conscious/etc. Descartes had God, and you have your Total Turing Test, neither of which are truly satisfactory to me (although I do have faith in God :-). As I understand it, TTT merely involves applying our practical solution of the other minds problem to AI systems. In other words, TTT says, "I'm not going to define how a system understands a language, but I'll know it when I see it." Meanwhile, I can turn around and say, "It sure acts like it understands, but look at the underlying architecture. It's a machine, and MACHINES CANNOT UNDERSTAND. (or it's a formal system, or it's non-biological, or it's only a simulation, or any other hokey excuse) Now we're at a standoff, where one believes that the given system does understand because it passed the TTT, and the other other just as firmly believes that it does not understand because the underlying architecture is incapable of believing. All because of the refusal to commit to a definition. Both camps hold different common sense notions of understanding, one based more on behavior and the other based more on underlying architecture. Both are practical solutions to the other minds problem, and both predict different things for this one solution. Which one is right? >(2) The TTT (fine-tuned eventually to include neuronal "behavior" too) >encompasses all the available empirical data for the mind-modeler. >(The only other data are subjective data, and I advocate methodological >epiphenomenalism with respect to those.) The LTT, on the other >hand, is just an arbitrary subset of the available empirical data. I don't know about you, but I certainly don't include neuronal behavior in any of my practical solutions to the other minds problem. And how can you make sense out of such data without having some theory of understanding, besides our intuitive, subjective ones? I know that I don't have any meaningful intuitions about neuronal behavior. Could it be that maybe deep down inside, you might think that a theory of understanding would be useful? And maybe there is in fact a definitional issue in here after all? >" Let's take a variation of the Chinese room where the purpose of the >" room is to interpret [Chinese] BASIC instead of to understand >" Chinese... Is it fair to conclude, then, that the system of the person >" in the Chinese BASIC room and her bits of paper is not really >" interpreting BASIC?... Now who's in the grip of whose ideology? > >The suspicious reader who might think I stacked the cards by clipping >out the ARGUMENTS in pasting together the above excerpt will be >surprised to see, upon reading the entire original posting, that >there ARE no arguments: The Chinese Room has simply been reformulated >in Chinese Basic, and voila! (There's also a double-entendre here >on the syntactic vs. the mentalistic meaning of "interpret.") Mere >repetition of credos is yet another symptom of ideological grippe. Thank you for pointing out that Searle (and I) aren't really arguing here, but merely following different ideologies to different conclusions. As for the double meaning of "interpret," I'll take the "practical" meaning: "*Interpreting BASIC* means *Running my program* and I'll know it when I see it." :-) -Alex
engelson@cs.yale.edu (Sean Engelson) (03/03/89)
In article <2483@crete.cs.glasgow.ac.uk>, gilbert@cs (Gilbert Cockton) writes: >In article <51123@yale-celray.yale.UUCP> engelson@cs.yale.edu (Sean Engelson) writes: >>(Searle + rules) understanding of Chinese? It seems that to >>demonstrate or refute the position of understanding being demonstrable >>purely through I/O behavior, one must have an effective definition of >>understanding. By effective I mean one that does not beg the >>question, i.e. by defining understanding to be symbol-processing, or >>conversely, to be that which humans do. > >Sorry, but your constraints are a little weird. Understanding *IS* >what humans do. >It *MAY* involve symbol processing. What question is begged? What is >an effectiver >definition? What I meant was rather "that which _only_ humans do", i.e. a priori ruling out any form of non-human understanding. >Look how well physicists manage with "force", "charge", "gravity". >You cannot ask commentators on humanity for "definitions" that are >any less (fast >and) loose than those used by commentators on nature. But a physicist can give me a simple and effective procedure by which I can measure the charge of a body, or the force of gravity. I have seen no such procedure of criterion for recognising understanding, other than I/O equivalence with that which we call understanding in humans. Under that criterion, the Chinese Room understands. >The question for the strong AI brigade is: > >"Given the normal usage of understanding, what grounds are there for >attributing it >to computers, and why bother anyway" > >While we're at it, what about those halucinogenic thermostats with beliefs. >Whatever it was, don't eat it again :-) The normal usage of understanding is that if (a) someone says they understand, and (b) they act as if they do, then they understand. Unless you have a theory of understanding that rules out physical symbol systems (and neural nets are symbol systems too!), then I see no reason not to attribute understanding to computers. Why bother anyway? Excellent question. I see no real purpose in it, except that the anti-attribution thereof is used as a criticism of AI, incorrectly. If it looks like a duck, and it acts like a duck, and it quacks like a duck, then what does it matter if it understands in an epistomological sense or not? ---------------------------------------------------------------------- Sean Philip Engelson, Gradual Student Who is he that desires life, Yale Department of Computer Science Wishing many happy days? Box 2158 Yale Station Curb your tongue from evil, New Haven, CT 06520 And your lips from speaking (203) 432-1239 falsehood. ---------------------------------------------------------------------- Nondeterminism means never having to say you're wrong.
arm@ihlpb.ATT.COM (Macalalad) (03/03/89)
In article <Feb.26.15.55.22.1989.7914@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >There are two senses in which Searle is advocating "looking inside": One >is to look at the functions of the brain, because we have pretty good >reason to believe that candidates with brains have minds (because, as I >would put it, candidates with brains can pass the TTT). The second sense >of "inside" is the first-person test for subjectivity, which we can all >perform on ourselves. It's THAT "causal power" that he reminds us >brains have but symbol-crunchers do not. My reply is that candidates >OTHER than the brain that can pass the TTT (if and when we come up with >any) are immune to his Chinese Room Argument that they cannot have a >mind (though, of course, I repeat, no objective test can demonstrate >that anyone, EVEN ourselves, has a mind). Searle's argument against >(hypothetical) candidates that pass the LTT only, with symbols only, >is decisive, however. AHA! We finally have a definition from Stevan about understanding, or at least a prerequisite to understanding, namely, the ability to introspect. In light of this prerequisite, let me see if I understand Searle's argument: (1) In order to understand, a system must be able to introspect. (Sort of like "I think, therefore I am.") (2) A given entity is the best judge of what it can or cannot understand, given that the entity is capable of introspection. (3) From (1), in order for the Chinese room to understand, there must be an introspecting agent. (4) The human in the Chinese room is clearly capable of introspection. (If not, substitute yourself for the human in the Chinese room.) (5) From (3) and (4), the human is the introspecting agent in the formal system, if indeed the formal system has one. (6) From (2) and (5), the human is the best judge of what the system can or cannot understand. (7) The human, upon introspection, concludes that he or she does not understand Chinese. (8) From (6) and (7), the system does not understand Chinese, although it appears to outside observers that it can. Do I fairly characterize Searle's argument? If so, I think that (5) is clearly the weak point in the chain. And although I've seen Stevan staunchly defend some of the other points, which I personally don't have serious problems with, I haven't really seen him address this point, other than to argue that it is obvious to everyone who hasn't been brainwashed by a Yale education. Being a Yalie myself, I wonder if Stevan would run through the argument a bit slower for my benefit. The systems reply focuses on the weakness of (5), stating that the introspective agent is not the human, but the formal system. If we then say that the formal system is incapable of introspection, then why are we going through the exercise of Searle's argument? Aren't we assuming that the formal system is incapable of understanding in order to prove that it's incapable of understanding? Isn't the hidden premise of (5) really that if the formal system is capable of introspection, then the agent of introspection must necessarily be the agent which executes the rules? To that hidden premise comes the argument that neurons are the agents of the brain which execute our "rules" of understanding, yet they certainly don't seem to be introspective. So unless Stevan can show me otherwise, I can't see how Searle's argument is logically compelling. It isn't even intuitively compelling to me, but then again, I'm in the grips of an ideology, and a Yalie on top of that. :-) >I've always thought this reasoning was quite easy to understand, but from >the fact that very few people have given me any objective evidence that >they've understood it, I've concluded that it must be difficult to >understand. Maybe by trying to put it slightly differently each time, >tailoring it to the latest misunderstanding, I'll succeed in making it >understood eventually... I'm getting optimistic here, Stevan. I do believe we're making some progress. Maybe a few more iterations before we reach an agreement? Nah. -Alex
ellis@unix.SRI.COM (Michael Ellis) (03/03/89)
> Jeff Dalton >> David Sher >>Does anyone believe that they can build a machine with a soul? It is >>just as easy to build in Searle's "understanding." > >It's certainly true that it's hard to see what could ever convince >Searle that anything had understanding. Then you missed something. Searle is *already convinced* that at least: 1. Searle has it 2. Other humans have it -michael
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/03/89)
arm@ihlpb.ATT.COM (Macalalad) of AT&T Bell Laboratories writes:
" Argument: In order to come to any resolution about what systems can
" or cannot understand, we need an objective theory of understanding,
" rather than the behaviorist "I'll know it when I see it" tests such
" as the Linguistic Turing Test (LTT) or the Total Turing Test (TTT).
Counterargument: To ascertain (beyond reasonable doubt) that a system
CANNOT understand, you don't need a theory. Searle's argument is a case
in point: If Searle (or you, or me) does exactly what the computer does
but does not understand, then the computer does not understand.
" you may be totally confident that you know when you understand
" a language, but to conclude that you know when another entity understands
" a language is a leap that I'm not quite ready to make.
No need to make the leap. Just know when you yourself don't understand
(in doing exactly what the symbol cruncher does) and infer that
nothing/no-one else doing exactly the same thing can be understanding
either.
" As I understand it, TTT merely involves applying our practical solution
" of the other minds problem to AI systems. In other words, TTT says,
" "I'm not going to define how a system understands a language, but
" I'll know it when I see it."
No. The logic of the TTT is this: I have no other basis but the TTT for
my confidence that other PEOPLE have minds, therefore it would be arbitrary
of me to ask MORE of robots. This is only a practical, not a principled
solution to the other-minds problem, however. Hence the same uncertainty
remains, in both cases (human and robot).
" I can turn around and say, "It sure acts like it understands, but look
" at the underlying architecture. It's a machine, and MACHINES CANNOT
" UNDERSTAND. (or it's a formal system, or it's non-biological, or it's
" only a simulation, or any other hokey excuse)... Now we're at a
" standoff, where one believes that the given system does understand
" because it passed the TTT, and the other other just as firmly believes
" that it does not understand because the underlying architecture is
" incapable of believing. All because of the refusal to commit to a
" definition.
To say "machines can't understand" is to beg the question. (We don't
even know what "machines" are -- and aren't -- yet.) "Wrong
architecture" simpliciter is arbitrary too: What's the "right"
architecture? No one knows what the brain's functional "architecture"
is, or what aspects of it are necessary or sufficient for having a
mind. To say it doesn't understand because its nonbiological is also
to beg the question.
To say it doesn't understand because it's just doing formal symbol
manipulation calls for an ARGUMENT: Searle has given one. ("Simulation"
is equivocal; even Searle's "simulated forest fires don't burn"
argument is enough to handle that -- but it all boils down to whether
symbol manipulation alone is enough not only to simulate the mind but
to implement it.)
So it still has nothing to do with definition; and there's clearly
room for plenty of hokeyness on both sides. (You made a crucial
error, by the way, in referring to the TTT above; you should have
said the LTT. That's the one the two sides are disagreeing on, and
that's the one Searle's argument is decisive against. The TTT is
immune to Searle's argument and I've so far heard no non-hokey objection
to it.)
" I don't know about you, but I certainly don't include neuronal behavior
" in any of my practical solutions to the other minds problem.
I certainly don't either. That's why I don't accept "wrong internal
functions" as an argument in itself: We have no idea what internal
functions are "right" or why; and only the TTT can lead us to an
answer. However, as I said, down the road a ways toward TTT utopia,
brain "performance" may eventually provide a useful "fine tuning"
variable on our near-asymptotic candidate. (The main problem with
brain function when you're far from utopia -- besides the fact that
we don't know what it is, and have no idea how we could find out
by peeking and poking at the brain -- is that we don't even know
what aspects of it are relevant and what aspects are irrelevant.)
Ref: Harnad (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
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(609)-921-7771harnad@elbereth.rutgers.edu (Stevan Harnad) (03/03/89)
arm@ihlpb.ATT.COM (Macalalad) of AT&T Bell Laboratories writes:
" (1) In order to understand, a system must be able to introspect.
"Introspect"? Let's not unnecessarily multiply our mysteries: In order
to understand, a candidate must experience [ = feel, undergo the
subjective state of] what we experience [feel, undergo the subjective
state of] when we understand. (Prerequisite: It must be able to
EXPERIENCE [feel, undergo subjective states] simpliciter.)
" (2) A given entity is the best judge of what it can or cannot understand,
" given that the entity is capable of introspection.
If a candidate is capable of experience at all, it is the only one
that can know it.
" (3) From (1), in order for the Chinese room to understand, there must
" be an introspecting agent.
All this fancy formalism and inference is not necessary: For a candidate
to understand, someone/something must be experiencing understanding.
" (4) The human in the Chinese room is clearly capable of introspection.
" (If not, substitute yourself for the human in the Chinese room.)
Agreed -- except for the unnecessary, uninformative extra mystery
term "introspection": Humans can understand (and in this case,
understand English but not Chinese).
" (5) From (3) and (4), the human is the introspecting agent in the formal
" system, if indeed the formal system has one.
This is getting too complicated. What does "having an introspecting
agent" mean? Why clutter a simple, straightforward argument with
arbitrary, point-obscuring extra baggage? Searle is in the room, doing
everything the computer does, but understanding no Chinese. Therefore
the computer understands no Chinese (or anything at all) when it's
doing the very same thing.
" (6) From (2) and (5), the human is the best judge of what the system can
" or cannot understand.
"The human," in case you've forgotten, is the only one in there, besides
the chalk and blackboards! I'll let you be the judge of how good a judge
the chalk, or Searle-plus-chalk makes...
" (7) The human, upon introspection, concludes that he or she does not
" understand Chinese.
Have it your way. I'm satisfied to say the only thing in sight (and the
only one doing anything) doesn't understand Chinese.
" (8) From (6) and (7), the system does not understand Chinese, although
" it appears to outside observers that it can.
Don't forget that there was a PREMISE in all this, which Searle
adopted, from Strong AI, FOR THE SAKE OF ARGUMENT, which was that the
LTT (sic) could be successfully passed (till doomsday!) by symbol
manipulation alone. Hence you are merely reading back the premise when
you remind us of the surprising fact that the Chinese LTT is being
passed, i.e., the symbols coming out are consistently and coherently
interpretable as discourse from an out-of-sight Chinese interlocutor.
It is of course quite possible that this premise is false. (I, for one,
believe it is false, and in my paper I give reasons why.) But repeating
the premise alone does not invalidate Searle's argument: On the contrary,
Searle's argument goes some way toward invalidating the LTT.
" Do I fairly characterize Searle's argument? If so, I think that (5) is
" clearly the weak point in the chain. And although I've seen Stevan
" staunchly defend some of the other points, which I personally don't
" have serious problems with, I haven't really seen him address this
" point, other than to argue that it is obvious to everyone who hasn't
" been brainwashed by a Yale education.
You characterized a simple argument in a fairly complicated way, with
enough arbitrary extra baggage to obscure its simple point. Reread my
comment after (5) above and try to think back to life before Yale...
" The systems reply focuses on the weakness of (5), stating that the
" introspective agent is not the human, but the formal system. If we
" then say that the formal system is incapable of introspection, then
" why are we going through the exercise of Searle's argument? Aren't
" we assuming that the formal system is incapable of understanding in
" order to prove that it's incapable of understanding?
Look, do you think an inert book of rules is capable of understanding?
If you do, then you'll have no trouble believing that stones, chalk,
constellations and tea-leaves are capable of understanding too, and I
certainly won't be able to prove you wrong. (Animism or panpsychism --
the belief that anything and everything can have a mind -- is the other
side of the other-minds problem.) But if we assume that we need a bit
more than that -- say, the ability to pass the LTT [sic] -- then
Searle's Argument is there to show us that that's just not good enough,
because he can pass the LTT for Chinese without understanding Chinese.
And he's all there is to the "system."
Ref: Harnad (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
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srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771geb@cadre.dsl.PITTSBURGH.EDU (Gordon E. Banks) (03/03/89)
In article <232@nbires.nbi.com> matt@nbires.UUCP (Matthew Meighan) writes: > >My own view is that subjective experience does not arise from the >brain at all, but vice versa -- that the brain, and the rest of the >physical body, is evolved by consciousness to give itself a vehicle >with which to interact with other consiousnesses. Understanding >and subjective experience do not exist in the brain at all, but in the >mind, of which the brain is just the most obvious and least-subtle part. > Of course, Lord Berkeley demonstrated long ago that all reality may be subjective and we can't know anything for certain. But once that interesting speculation is made, you can't get much further. If the brain is just part of the mind, what are the other parts? The spirit, soul or some other animus? Some other part of the body? Something that isn't part of the body? >This viewpoint is plainly not provable -- that is, I can't prove it to >YOU from MY experience. For me, it is both 'subjectively' true because >it is what I feel, and 'objectively' true because I have observed >phenomena I can't explain any other way. Exactly what were those phenomena. Perhaps others can explain them as arising from the brain. Just because you can't explain them doesn't mean they are inexplicable. Or are they also something you can not even communicate, something mystical? (If so, follow ups to talk.religion.misc). > >My real point, though, is that your view that consciousness "arises" >from the physical brain is as purely subjective as mine that it is the >other way around. It seems to me that this assertion is a leap of >faith, resembling more a religious conviction than a scientific one. > Not so. The idea that the mind comes from the brain is scientific and is substantiated by evidence that damage to the brain causes damage to the "mind". In fact, all of the cognitive processes that most people think of as being the mind can be damaged or abolished by lesions made to specific parts of the brain. Thus a properly functioning brain is necessary to consciousness and to the elements of human personality. Is it sufficient? We won't know until we create a brain and it acts conscious. Even then, you might argue that even though we created the brain, God sent a soul to animate it. So the argument could still go on, although its weight would be diminished. >one question we can answer the other) we should take the fact that >understanding does NOT emerge in computer programs as evidence that it >does NOT emerge in brains, either. > Oh, nonsense! The brain has 10^12 neurons and many more connections. None of our puny computers (mostly von Neumann to boot) or programs have come close to such an engine. About the best we could model now is a toad (see Michael Arbib's Rana Computatrix), and that requires a supercomputer to run.
mike@arizona.edu (Mike Coffin) (03/04/89)
From article <Mar.2.23.56.36.1989.28884@elbereth.rutgers.edu> (Stevan Harnad): > Searle is in the room, doing everything the computer does, but > understanding no Chinese. Therefore the computer understands no > Chinese (or anything at all) when it's doing the very same thing. So what? No one said that a bare stored-program computer, without benefit of algorithms, can understand Chinese. And no one says that the algorithm, in book form, understands Chinese. Does this prove that the combination of the two can't understand anything? Why? To me, this little lemma seems to be the the crux of the whole "proof." I haven't seen it addressed yet, much less demonstrated. You DO need to show this! There is ample evidence that a computer running an algorithm can have properties that neither the computer (without algorithm) nor the algorithm (without computer) have. -- Mike Coffin mike@arizona.edu Univ. of Ariz. Dept. of Comp. Sci. {allegra,cmcl2}!arizona!mike Tucson, AZ 85721 (602)621-2858
gss@edsdrd.eds.com (Gary Schiltz) (03/04/89)
In article <7653@venera.isi.edu>, smoliar@vaxa.isi.edu (Stephen Smoliar) writes: -> In article <125@arcturus.edsdrd.eds.com> gss@edsdrd.eds.com (Gary Schiltz) -> writes: -> > -> > [anecdote about doing calculus without "understanding" calculus] -> > -> -> This brings me to my second point. At his "gut level" Gary felt, -> introspectively, that he really did not understand calculus. ... -> ... -> ... I, for one, would like Gary to attempt -> to probe further as to just WHY, at that gut level, he felt understanding was -> eluding him. Did it have to do with problems he could not solve? Did his -> eyes glaze over whenever he saw integral signs in the pages of a book? Did -> he just feel that we was struggling more than his fellow students to solve -> problems? Perhaps if we probe these matters deeper, we may yet return to -> my initial point: that Gary's "gut level feeling" may leave something to -> be desired as a criterion for understanding. I'm not sure how far this is probing, but ... I feel I didn't understand calculus because I didn't know what in the "real world" was being represented by the equations I was solving. For example, I didn't know that dY/dX represent the change in Y given an infinitely small change in X. I just knew that "dY/dX" was referred to as the "derivative of Y with respect to X", that Y and X were variables and that the derivative could be generated for an equation by manipulating it in a certain way. I also happened to have picked up a certain amount of knowledge about how to map word problems into equations that could be differentiated and solved. My feeling that I lacked understanding is not the result of lack of competence. I did have a lack of competence, but that's a separate issue. The real issue is my lack of a mental map between a method (differentiation) and something in the real world (determining instantaneous rate of change). -> ... (One last question to Gary: -> Can you identify a moment at which you said, "NOW I understand calculus;" -> and can you recall the circumstances of that moment.) The closest I can remember is that in the "second time around" course, I formulated the equations to describe word problems much more easily. This was the result of two skills I had obtained. First, I could visualize the solution to a word problem in terms of trying to find out about the rate of change of some quantity (velocity, for instance) with respect to something else (time, for instance). To me, this seems to boil down to an ability to analyze a physical system and create an abstract model of it. I believe I had this skill even the first time I took the course. Second, I understood what derivatives stand for in the real world, i.e. rates of change. This is the "understanding" that I lacked in the first course. Without this piece of knowledge, I could not come up with the equations to be used in my abstract model of a problem in order to solve that problem. Another trivial fact (possibly unnecessary): I use calculus so seldom these days that I'm not sure I understand it any better than I did the first time I took it over ten years ago. In any event, I think I understand understanding even less than I understand calculus. Oh well, as Kurt Vonnegut, Jr. might say, "Hi Ho." ----- /\ What cheer, /\ | Gary Schiltz, EDS R&D, 3551 Hamlin Road | / o< cheer, <o \ | Auburn Hills, MI 48057, (313) 370-1737 | \\/ ) / cheer, \ ( \// | gss@edsdrd.eds.com | \ / cheer!!! \ / | "Have bird will watch ..." |
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (03/04/89)
From article <Mar.2.01.19.30.1989.14279@elbereth.rutgers.edu>, by harnad@elbereth.rutgers.edu (Stevan Harnad): " ... " It's amazing to me how trapped people can be in their preconceptions. I confess. It's just this silly Yale-propagated ideology 'science' that gave me this urge to seek theory + evidence lurking somewhere behind your words. I think I'm getting on the right wavelength though, at last. " ... " I could do exactly the same (nonlinguistic) number on the distinction " between pain and tissue damage, or, for that matter, the distinction " between a left- and a right-sided ache. Yes, I think you could. Let me test my understanding by giving it a try myself, but I'll choose a different example. There's a difference, I shall claim, a real substantive distinction, between understanding-in-the-morning and understanding-in-the-afternoon. What's my evidence? Consider "I finally understood Harnad at 3pm." The word 'understood' here cannot mean understood-in-the-morning. That seems very clear (clearer even than the "I don't seem to be in pain" example). Does this have to do with the language category of the phrase 'at 3pm'? No, since it is straightforward to construct similar examples with different syntactic structure. It has to do with the *reference* of 'at 3pm'. So it's not linguistic. Say, I could get to like this kind of theory. So much easier to find evidence! Greg, lee@uhccux.uhcc.hawaii.edu
jackson@freyja.css.gov (Jerry Jackson) (03/04/89)
This is mostly intended for Steven Harnad.... I tried a few months back to convince people in this newsgroup that there was a difference between say: the *experience* of pain and the signal travelling through the nervous system.. or the *experience* of seeing blue and anything you could possibly tell a blind person about it. My conclusion: Most people who post to this newsgroup have no subjective experience. No wonder you can't get your point across. You have obviously been making *very* clear sense, so I can't come up with any other explanation. :-) I wonder if Mr. Lee considers the effect of hitting his thumb with a hammer linguistic. If I said, "Gee, Mr. Lee, does that *hurt*?".. he would probably reply one of two things: a) It seems to hurt, but I could be wrong.. or b) No, the pain is merely a linguistic abstraction Once again, anyone who has not seen your point by now probably never will (or at least not through more attempts to convince them) I speak from personal experience. Please continue trying if you are up to it, though, since I (and probably many others) find your postings refreshingly clear, well thought out, and interesting. Now, because I'm a glutton for punishment... Does anyone really think someone can be wrong about whether or not they are in pain? Wouldn't it seem really odd to respond to the statement: "I just stubbed my toe and boy does it hurt!" with: "No it doesn't." It is in this sense that Mr. Harnad intends you take the statement "I understand." You might be wrong in an objective sense... your model might be inaccurate. I think everyone has had the experience of insight, though. You know what I mean. It's what you are referring to when someone asks you if you understand and you say "Yes". Do you understand? --Jerry Jackson
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/04/89)
mike@arizona.edu (Mike Coffin) of U of Arizona CS Dept, Tucson writes:
" No one said that a bare stored-program computer, without benefit of
" algorithms, can understand Chinese. And no one says that the algorithm,
" in book form understands Chinese. Does this prove that the combination
" of the two can't understand anything? Why?... a computer running an
" algorithm can have properties that neither the computer (without
" algorithm) nor the algorithm (without computer) have.
I completely agree with the last proposition, except that understanding
is not one of those properties. Why? Because when Searle stands in for
the computer, doing everything it does, executing all of its algorithms,
he does not understand. Hence neither can the computer understand, when
it does exactly the same thing.
Ref: Searle, J. (1980) Minds, Brains and Programs. Behavioral and Brain
Sciences 3: 417-457.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
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(609)-921-7771geddis@polya.Stanford.EDU (Donald F. Geddis) (03/04/89)
In article <Mar.2.23.55.02.1989.28807@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >If Searle (or you, or me) does exactly what the computer does >but does not understand, then the computer does not understand. True enough, but then you are defining the "computer" to be the dumb processor that interprets the rules. No one claimed that the processor (by itself) *did* understand. I still haven't heard a satisfactory rebuttal to the "Systems Reply", namely that (Searle + Rules) understands, whereas just (Searle) doesn't. [To use your analogy: (Computer Processor + Symbolic Rules) understands, but just (Computer Processor) doesn't.] >Just know when you yourself don't understand >(in doing exactly what the symbol cruncher does) and infer that >nothing/no-one else doing exactly the same thing can be understanding >either. But we *can't* imagine what it would be like to process the Chinese Room rules, because any set of rules that passed the Turing Test would be far to large and complex by orders upon orders of magnitudes for a person to actually (as opposed to simply in the thought experiment) process them. And so this is a case where our intuitions fail us miserably. >The logic of the TTT is this: I have no other basis but the TTT for >my confidence that other PEOPLE have minds, therefore it would be arbitrary >of me to ask MORE of robots. This is only a practical, not a principled >solution to the other-minds problem, however. Hence the same uncertainty >remains, in both cases (human and robot). Not quite true. I can use a biological argument with humans as well, and say "they evolved (via evolution) the same way I did, and we belong to the same species, and (as beings) we were conceived and developed the same way, so if I can think, then they probably can too." Robots don't get quite that close and argument in their favor. But in any case, I don't think that those who argue for the Turing Test (your LTT) would disagree that your TTT works as well, since it encompases the original test. It is harder to pass. I'm not convinced that that is an advantage, though. >That's the one [LTT] the two sides are disagreeing on, and >that's the one Searle's argument is decisive against. The TTT is >immune to Searle's argument and I've so far heard no non-hokey objection >to it. Go through this again, please? I think that Searle doesn't have an argument at all, but I fail to see how your TTT test makes any difference at all to his analysis. At any rate, it certainly is not obvious that Searle's argument is decisive, and that your reformulation is immune. But I'd be interested in hearing your justifications. -- Don Geddis -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
geddis@polya.Stanford.EDU (Donald F. Geddis) (03/04/89)
In article <Mar.2.23.56.36.1989.28884@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >"The human," in case you've forgotten, is the only one in there [Chinese Room], besides >the chalk and blackboards! I'll let you be the judge of how good a judge >the chalk, or Searle-plus-chalk makes... Since the Systems Reply is exactly that Searle-plus-chalk-plus-blackboard-plus- rules *does* understand, doesn't this "answer" seem a little unfair. Rather than present arguments against the Systems Reply, Stevan seems to be appealing to our intuitive sense of "well, come on, *everyone* knows that this is foolish". But a good many well-educated people who have thought hard about the problem don't consider it to be foolish, so a little more effort on the rebuttal is required... >Don't forget that there was a PREMISE in all this, which Searle >adopted, from Strong AI, FOR THE SAKE OF ARGUMENT, which was that the >LTT (sic) could be successfully passed (till doomsday!) by symbol >manipulation alone. [without being embedded with sensors, etc.] >... >It is of course quite possible that this premise is false. (I, for one, >believe it is false, and in my paper I give reasons why.) Strangely enough, I agree with your prediction, and with your solution. But that is not important for the Chinese Room argument. You could start with a robot that is embedded in the world, and after it achieves full understanding (the same way humans do: learning within the context of a society), then you can disconnect the sensors and effectors and leave only a teletype to the outside world. Sounds a lot like Stephen Hawking in real life, no? Suddenly, the LTT (i.e., the original Turing Test) returns. Why make the claim that the understand, to which you agreed before, suddenly disappears? In other words, while you may be correct that understanding (getting the proper set of rules) is impossible without being embedded in the world, why make this part of the test? It's just an implementation issue... >Look, do you think an inert book of rules is capable of understanding? >If you do, then you'll have no trouble believing that stones, chalk, >constellations and tea-leaves are capable of understanding too, and I >certainly won't be able to prove you wrong. Not at all. The complexities of the systems varies widely. In particular, some (very small fraction) of things can pass the Turing Test (LTT). > (Animism or panpsychism -- >the belief that anything and everything can have a mind -- is the other >side of the other-minds problem.) But if we assume that we need a bit >more than that -- say, the ability to pass the LTT [sic] -- then >Searle's Argument is there to show us that that's just not good enough, >because he can pass the LTT for Chinese without understanding Chinese. Tsk, tsk. No he can't. The Chinese room does. >And he's all there is to the "system." Completely, 100%, false. Wrong. Incorrect. The Chinese Room contains Searle AND THE RULES. And the system as a whole DOES understand, as evidenced by the Chinese answers to Chinese questions. -- Don Geddis -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
mike@arizona.edu (Mike Coffin) (03/05/89)
Stevan Harnad writes: > I completely agree with the last proposition, except that understanding > is not one of those properties. Why? Because when Searle stands in for > the computer, doing everything it does, executing all of its algorithms, > he does not understand. Hence neither can the computer understand, when > it does exactly the same thing. True, but no one said he (or it) did understand. The argument is that the SYSTEM --- Searle, or the computer, running an algorithm --- understands. Searle corresponds to the bare machine. Asking Searle if he understands is equivalent to running a debugger on the "Chinese algorithm"; the fact that the debugger doesn't understand Chinese is not an argument that the rest of the system doesn't. It is interesting that you consistently refuse to talk about the system as an entity unto itself. You do this in spite of all the evidence of your senses --- remember, this system passes the Turing test! You have this impressive system in front of you; it certainly seems to understand Chinese; Searle certainly doesn't; the rules by themselves certainly don't. Yet you ignore the evidence and insist on talking about components of the system as if they were the system. It almost looks like you're in the grips of an ideology :-) -- Mike Coffin mike@arizona.edu Univ. of Ariz. Dept. of Comp. Sci. {allegra,cmcl2}!arizona!mike Tucson, AZ 85721 (602)621-2858
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (03/05/89)
From article <330@esosun.UUCP>, by jackson@freyja.css.gov (Jerry Jackson): " ... " Now, because I'm a glutton for punishment... Does anyone really think " someone can be wrong about whether or not they are in pain? Wouldn't " it seem really odd to respond to the statement: "I just stubbed my toe " and boy does it hurt!" with: "No it doesn't." It is in this sense that No it doesn't ... did you forget about the amputation, Jerry? " Mr. Harnad intends you take the statement "I understand." You might ... It helps to keep separate issues separate. There's the pecularity of subjective experience and related linguistic peculiarities: for instance, there *is* evidence that 'I think' is different from 'he thinks'. And there is finding a distinction between two senses of 'understand' and making one. I contended that although you can make one (of course), you can't find one. It's worth keeping straight about that, because substantial conclusions can't follow from mere definitions. And then there's Harnad's attempted defense of Searle which exploits the supposed distinction between two senses of understand. That defense proceeds by positing that I don't understand Chinese (true), writing a few paragraphs during which the reader is distracted enough to forget the supposed distinction, and concluding that "of course" the CR doesn't understand Chinese. If you remember the distinction, though, you see that in the posited sense, the conclusion follows only from the fact that I am not the CR (even if I'm in it), and for that matter no one in the wide world understands Chinese, in *this* sense of understand. So it's just a sophistry. Other participants in the discussion have pointed this out. And then there's Searle's argument itself. I can accept a distinction between subjective and objective (which I do) without accepting that there is such a distinction to be *found* in the *particular* case of 'understand', though I can still accept *making* such a distinction. Independently of that question I could have accepted Harnad's argument consistently, if I had not noticed his equivocation. In spite of Harnad's illogic, I might still be able to accept Searle's argument (though I don't). Greg, lee@uhccux.uhcc.hawaii.edu
bwk@mbunix.mitre.org (Barry W. Kort) (03/05/89)
From lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii:
> What are you talking about?
In reading the dialogue between Greg and Stevan, I have the subjective
feeling that I do not understand English.
I can parse the sentences, but I cannot reliably extract their
semantic content. It seems that I am not alone.
Please tell Searle to cross me off the list of entities who undertand.
And now, if you will excuse me, I'm going back to my room.
--Barry Kortbwk@mbunix.mitre.org (Barry W. Kort) (03/05/89)
In article <3369@uhccux.uhcc.hawaii.edu> lee@uhccux.uhcc.hawaii.edu (Greg Lee) writes: > "I finally understood Harnad at 3pm." Aha! This piece of evidence confirms my theory that we use the word "understand" to mean "able to gain understanding" (as opposed to "has a fixed amount of understanding"). Evidently, we are using the positive first derivative of the function K(t) to denote understanding, where K(t) is the accumulated Knowledge as a function of time. Curiously, I define "information" as delta K, and "learning" or "knowledge acquisition" as dK/dt. But the most interesting part of this model, is that I measure emotional intensity, E, the same way: E(t) = dK(t)/dt Understand? --Barry Kort
bwk@mbunix.mitre.org (Barry W. Kort) (03/05/89)
In article <330@esosun.UUCP> jackson@freyja.css.gov (Jerry Jackson) writes: > Now, because I'm a glutton for punishment... Does anyone really think > someone can be wrong about whether or not they are in pain? Wouldn't > it seem really odd to respond to the statement: "I just stubbed my toe > and boy does it hurt!" with: "No it doesn't." Amputees report feeling "phantom limb pain". Their toe does hurt. Except that they have no toe. Physiologically, we understand that pain signals are still arriving at the somasthetic cortex and lighting up the map sector labelled "left great toe". These examples reveal that we have trouble distinguishing an event (I stubbed my toe, which is now black and blue, and bleeding) from the message arriving at the brains ("the sensors in the left great toe are reporting a disaster"). Where is the pain? Is it in the toe or in the message? --Barry Kort "This message will self-destruct in one week."
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/06/89)
bwk@mbunix.mitre.org (Barry W. Kort) asked: " Perhaps Stevan can clarify this point for us, because I believe " it is pivotal. In Searle's thought experiment, are the rules " immutable, or do they evolve as a function of the information " contained in the Chinese stories?... To my mind, a system which " understands is a system which integrates new information into an " expanding knowledge base, and this includes new and improved " information-processing techniques (i.e., the "rules"). " When we talk about "understanding" in human terms, don't we really " mean the ability to gain understanding (as opposed to merely having " a fixed amount of understanding)? (1) The ability to "learn" is a necessary but not a sufficient condition for having a (normal) mind. (2) In Searle's thought experiment, as long as everything that's going on is PURELY SYMBOLIC (symbols in, symbols out, symbol-crunching in between) it does not matter how you interpret the symbolic goings on -- as a conversation, as "learning," as rule-updating, as what have you. The punchline's the same: Since Searle can do it all without understanding, there's no understanding at all going on. -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/06/89)
geddis@polya.Stanford.EDU (Donald F. Geddis) of Stanford University wrote:
" you are defining the "computer" to be the dumb processor
" that interprets the rules. No one claimed that the processor (by itself)
" *did* understand. I still haven't heard a satisfactory rebuttal to the
" "Systems Reply", namely that (Searle + Rules) understands, whereas just
" (Searle) doesn't.
You've heard it. You just haven't understood it, because of a far-fetched
and circular notion to which you and many others have become committed
so strongly that the ability to un-commit in the face of logic and
counter-evidence seems to have been lost: There's no other entity, no
other eligible candidate for having a mind in the Chinese Room; nobody
home! "Searle + rules" is a piece of cog-sci-fi. Do you believe that I
could fail to understand, and alpha centauri could fail to understand,
but "I + alpha centauri" could compositely understand? Could we
compositely feel an itch that neither of us feels singly? If you don't
PRESUPPOSE the far-fetched notion that the Chinese Room Argument set
out to debunk in the first place, then you're less inclined to come
back with it by way of a reasoned rebuttal!
It's not that there CAN'T be a systems reply in principle: Searle COULD
have been a non-understanding part of an understanding system. He could
have been standing in, say, for the input and output of one neuron in a
real brain. Then the system WOULD have understood and Searle would not
have. But then neither would Searle have been performing ALL THE
FUNCTIONS that were the substrate of the understanding. So it would be
no surprise that he didn't understand. One of Searle's premises is that
he himself must do EVERYTHING the candidate mental model does, yet not
understand. (This is why my "robotic functionalist" counterargument
works, and why the TTT is immune to Searle's Argument.)
So you see, what Searle has really shown is not that no "systems
reply" is tenable, but that a systems reply is untenable in the case
of pure symbol-crunching, where Searle CAN do everything the system
does. Symbol-crunchers are the WRONG KIND OF SYSTEM for having a mind
(understanding, being intelligent [in the mental sense], etc.).
" But we *can't* imagine what it would be like to process the Chinese Room
" rules, because any set of rules that passed the Turing Test would be far
" to large and complex by orders upon orders of magnitudes for a person to
" actually (as opposed to simply in the thought experiment) process them.
See earlier replies on "speed and complexity." This is just
hand-waving. It's equivalent to taking a dumb toy model and saying
"Just more of the same will pass the TT and will have a mind." I think
the gap is not one of speed and complexity but missing,
yet-to-be-discovered substantive functional concepts (and not just
symbolic ones!).
" [To solve the practical "other-minds" problem] I can use a biological
" argument with humans [not just the TTT]... Robots don't get quite that
" close an argument in their favor.
We did many rounds on this on the Net 2 years ago: To synopsize:
(1) The predictive power of biological facts about organisms that pass
the TTT is parasitic on the fact that they pass the TTT. (Consider the
problems we start to have as we move to species further and further
than our own. -- Though let me hasten to add that I for one am fully
inclined to give other species the benefit of the doubt about having
minds, feeling pain, etc.) However, biological facts do, of course,
have a secondary corroborative power.
(2) We don't understand biological organisms or their brains
functionally, hence we couldn't even answer the question, in
principle, which one was a real organism and which was just a robotic
look-alike! Another reason why biology and brain function can't help
us much in our practical, everyday Turing Testing.
" I don't think that those who argue for the Turing Test (your LTT) would
" disagree that your TTT works as well, since it encompases the original
" test. It is harder to pass. I'm not convinced that that is an
" advantage, though.
You've missed the point. Of course the Lingustic Turing Test is a
subset of the Total Turing Test, and of course the whole Test would be
harder to pass. But my point (and it had supporting arguments) was
that it may well be that the only kind of device that could pass the
LTT in the first place would have to be a device that could likewise
pass the TTT, and that IN BOTH CASES it would have to draw essentially
on nonsymbolic internal functions.
" ["The TTT, unlike the LTT, is immune to Searle's Argument"]
" Go through this again, please? I think that Searle doesn't have an argument
" at all, but I fail to see how your TTT test makes any difference at all to
" his analysis. At any rate, it certainly is not obvious that Searle's
" argument is decisive, and that your reformulation is immune. But I'd be
" interested in hearing your justifications.
Here are points 3-7 from the summary and conclusions (p. 20 -21) of
Harnad (1989) Minds, Machines and Searle. Journal of Experimental and
Theoretical Artificial Intelligence" 1: 5-25 -- with apologies to
those who have seen them before (they have already been posted once
in their entirety at a poster's request).
(3) The Convergence Argument:
Searle fails to take underdetermination into account. All scientific
theories are underdetermined by their data; i.e., the data are
compatible with more than one theory. But as the data domain grows, the
degrees of freedom for alternative (equiparametric) theories shrink.
This "convergence" constraint applies to AI's "toy" linguistic and
robotic models too, as they approach the capacity to pass the Total
(asymptotic) Turing Test. Toy models are not modules.
(4) Brain Modeling versus Mind Modeling:
Searle also fails to appreciate that the brain itself can be understood
only through theoretical modeling, and that the boundary between brain
performance and body performance becomes arbitrary as one converges on
an asymptotic model of total human performance capacity.
(5) The Modularity Assumption:
Searle implicitly adopts a strong, untested "modularity" assumption to
the effect that certain functional parts of human cognitive performance
capacity (such as language) can be be successfully modeled
independently of the rest (such as perceptuomotor or "robotic" capacity).
This assumption may be false for models approaching the power and
generality needed to pass the Turing Test.
(6) The Linguistic Turing Test versus the Robot Turing Test:
Foundational issues in cognitive science depend critically on the truth
or falsity of such modularity assumptions. For example, the "teletype"
(linguistic) version of the Turing Test could in principle (though not
necessarily in practice) be implemented by formal symbol-manipulation
alone (symbols in, symbols out), whereas the robot version necessarily
calls for full causal powers of interaction with the outside world
(seeing, doing AND linguistic competence).
(7) The Transducer/Effector Argument:
Prior "robot" replies to Searle have not been principled ones. They
have added on robotic requirements as an arbitrary extra constraint. A
principled "transducer/effector" counterargument, however, can be based
on the logical fact that transduction is necessarily nonsymbolic,
drawing on analog and analog-to-digital functions that can only be
simulated, but not implemented, symbolically.
(8) Robotics and Causality:
Searle's argument hence fails logically for the robot version of the
Turing Test, for in simulating it he would either have to USE its
transducers and effectors (in which case he would not be simulating all
of its functions) or he would have to BE its transducers and effectors,
in which case he would indeed be duplicating their causal powers (of
seeing and doing).
(9) Symbolic Functionalism versus Robotic Functionalism:
If symbol-manipulation ("symbolic functionalism") cannot in principle
accomplish the functions of the transducer and effector surfaces, then
there is no reason why every function in between has to be symbolic
either. Nonsymbolic function may be essential to implementing minds and
may be a crucial constituent of the functional substrate of mental
states ("robotic functionalism"): In order to work as hypothesized
(i.e., to be able to pass the Turing Test), the functionalist
"brain-in-a-vat" may have to be more than just an isolated symbolic
"understanding" module -- perhaps even hybrid analog/symbolic all the
way through, as the real brain is, with the symbols "grounded"
bottom-up in nonsymbolic representations.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771harnad@elbereth.rutgers.edu (Stevan Harnad) (03/06/89)
geddis@polya.Stanford.EDU (Donald F. Geddis) of Stanford University wrote:
" the Systems Reply is exactly that Searle-plus-chalk-plus-blackboard
" -plus-rules *does* understand... Rather than present arguments against
" the Systems Reply, Stevan seems to be appealing to our intuitive sense
" of "well, come on, *everyone* knows that this is foolish". But a good
" many well-educated people who have thought hard about the problem don't
" consider it to be foolish, so a little more effort on the rebuttal is
" required...
Look, the "Systems Reply" and the reasoning, evidence and intuition
behind it, were precisely what Searle's Argument was formulated to
refute. It was already anticipated and explicitly discussed in
Searle's original target article. There's nobody home in the Chinese
Room except Searle! The rest is just chalk and blackboard. What do
the "Systems" enthusiasts reply? "So be it. Well then Searle + chalk
understands."
Now try to think back -- way, way back: Were you in the habit of
thinking that a person plus chalk could be understanding where the
person alone was failing to understand? (Sometimes certain kinds of
"education" can be a handicap...)
" Strangely enough, I agree with your prediction [that the premise that
" the LTT (sic) could be successfully passed (till doomsday!) by symbol
" manipulation alone is false], and with your solution. But that is not
" important for the Chinese Room argument. You could start with a robot
" that is embedded in the world, and after it achieves full understanding
" (the same way humans do: learning within the context of a society),
" then you can disconnect the sensors and effectors and leave only a
" teletype to the outside world. Sounds a lot like Stephen Hawking in
" real life, no? Suddenly, the LTT (i.e., the original Turing Test)
" returns.
You can't agree with my solution, because unfortunately you have not
understood it. If nonsymbolic functions are ESSENTIAL to passing both
the LTT and the TTT then it's not just a matter of sensors and
effectors connected to a symbol-crunching core. And Stephen Hawking
is not just a symbol-crunching core.
" while you may be correct that understanding (getting the proper set of
" rules) is impossible without being embedded in the world, why make this
" part of the test? It's just an implementation issue...
Because understanding may NOT be just a matter of "getting the proper
set of rules." If not, then even if a savvy robot jumped fully educated
out of the head of Zeus it could not pass the LTT or TTT without
internal NONSYMBOLIC functions; and if these were removed, it would no
longer be able to pass the LTT or TTT (and would no longer have a
mind). (Moreover, removing them would NOT be just a matter of yanking
off sensors and effectors from a symbol-cruncher.)
" ["Searle is all there is to the `system.'"] Completely, 100%, false.
" Wrong. Incorrect. The Chinese Room contains Searle AND THE RULES. And
" the system as a whole DOES understand, as evidenced by the Chinese
" answers to Chinese questions.
Unshakeable conviction. Who am I to try to counter the effects of
an education that gave rise to this? (I only timidly remind you again
that the possibility of successfully passing the LTT by
symbol-crunching alone was a hypothetical, so-far-counterfactual
PREMISE that Searle simply carried over from Strong AI for the sake of
argument. It may well be false; I've given reasons why it may be false.
In fact, Searle's Argument itself can be taken as one of the reasons
for concluding that it's false. Simply reiterating the premise cannot
serve as a logical counterargument against the VERY untoward conclusion
that FOLLOWS from the premise.)
Refs:
Searle J. (1980) Minds, Brains and Progams. Behavioral and Brain
Sciences 3: 417-457.
Harnad S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence" 1: 5-25
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771geddis@polya.Stanford.EDU (Donald F. Geddis) (03/06/89)
In article <Mar.5.13.17.35.1989.4486@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes (in reply to a posting of mine): >There's no other entity, no >other eligible candidate for having a mind in the Chinese Room; nobody >home! "Searle + rules" is a piece of cog-sci-fi. Do you believe that I >could fail to understand, and alpha centauri could fail to understand, >but "I + alpha centauri" could compositely understand? As a matter of fact, I do. So if you are appealing to intuitions here, it is obvious that we disagree about what is commonsense. So try another tack. >It's not that there CAN'T be a systems reply in principle: Searle COULD >have been a non-understanding part of an understanding system. He could >have been standing in, say, for the input and output of one neuron in a >real brain. Then the system WOULD have understood and Searle would not >have. But then neither would Searle have been performing ALL THE >FUNCTIONS that were the substrate of the understanding. So it would be >no surprise that he didn't understand. One of Searle's premises is that >he himself must do EVERYTHING the candidate mental model does, yet not >understand. (This is why my "robotic functionalist" counterargument >works, and why the TTT is immune to Searle's Argument.) OK, so a crucial point for you is that Searle can do it all himself, I assume by memorizing the rules. So now we have a very complex (and improbable, but we'll ignore that for the moment) entity in Searle's body. When we ask it, in Chinese, if it understands, the body replies "Yes, I do". When we ask, in English, if it understands Chinese, the body (using the small part of it that used to be Searle, before it memorized the rules), the body replies "Of course not! And I wrote a paper telling you this a long time ago!". Now I believe each reply to the same extent. Namely, that the whole entity (Searle + memorized rules) *does* understand Chinese, although a section of it (Searle by himself) doesn't. To try again: Now there are *two* minds in Searle's brain, just as there were two minds in the old Chinese Room (Searle and Searle + rules). I don't consider the lone Searle to be an authority on what Searle + Memorized Rules understands, although you seem to. Why? >See earlier replies on "speed and complexity." This is just >hand-waving. It's equivalent to taking a dumb toy model and saying >"Just more of the same will pass the TT and will have a mind." I think >the gap is not one of speed and complexity but missing, >yet-to-be-discovered substantive functional concepts (and not just >symbolic ones!). I agree that complexity arguments are not important for this thought experiement. But it is useful to be aware that our intuitions about how small rule sets function probably don't scale up well to large rule sets. In no way am I claiming that this is sufficient to create intelligence; I just don't want you to appeal to the triviality of small symbol processing in order to claim that large symbol processing won't work either. >You've missed the point. Of course the Lingustic Turing Test is a >subset of the Total Turing Test, and of course the whole Test would be >harder to pass. But my point (and it had supporting arguments) was >that it may well be that the only kind of device that could pass the >LTT in the first place would have to be a device that could likewise >pass the TTT, and that IN BOTH CASES it would have to draw essentially >on nonsymbolic internal functions. Probably true. (I agree.) But if that's the case, then just using the LTT is sufficient for judging intelligence, as Turing originally claimed. The point of the Turing Test was to eliminate non-cognitive things from the test, like "oh, it is colored green, and no human beings are colored green, so this must be the computer". We only want to judge cognitive ability. Whether this requires TTT ability is a problem for the engineers, not the judges. (As another point, while the Turing Test may be sufficient, it is not necessary. Turing made it too hard to pass. A hypothetical entity has to foolishly duplicate human errors, like arithemetic errors and long pauses for thinking. This needlessly eliminates intelligences that are comparable but not identical to human performance.) -- Don Geddis P.S. Thanks for the responses to my other questions. -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
bwk@mbunix.mitre.org (Barry W. Kort) (03/06/89)
In article <Mar.5.13.15.58.1989.4447@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > (1) The ability to "learn" is a necessary but not a sufficient > condition for having a (normal) mind. I understand that very well. > (2) In Searle's thought experiment, as long as everything that's going > on is PURELY SYMBOLIC (symbols in, symbols out, symbol-crunching in > between) it does not matter how you interpret the symbolic goings on -- > as a conversation, as "learning," as rule-updating, as what have you. > The punchline's the same: Since Searle can do it all without > understanding, there's no understanding at all going on. Stevan, I stared at your paragraph (2) for five minutes, trying to understand it. I must confess that, like Searle's thought experiment, I simply didn't understand it. --Barry Kort
krazy@claris.com (Jeff Erickson) (03/06/89)
Okay, forgive me if I'm being stupid, and e-mail me if you'd rather not
let this question start a new, long, ugly chain of massages on the same
old question.
Why CAN'T the rules "understand"? It looks (to me) like this is just a
piece of software being run through some rather copmlex hardware (the book,
Searle, the room, etc.).
Every claim I've read here in the last six days for "there is no under-
standing." bases that claim on the question "If there were, where does it
come from? Certainly not Searle (that's an axiom), and certainly not
the rule book (that's obvious)."
Why is it so obvious?
And if this IS obvious, where does MY understanding come from? Certainly
not the little neurons. That's obvious;-)
--
Any opinions you read here are only opinions in my opinion.
Jeff Erickson krazy@claris.com
"I'm so heppy I'm mizzabil!" -- Krazy Kat
------------------------------------------------------------------------------bwk@mbunix.mitre.org (Barry W. Kort) (03/06/89)
I would like to ask another question about the Chinese Room protocol. As given by Searle, the Chinese stories are not illustrated. But we all know that children learn to read using illustrated stories. The text is intimately linked to the pictures. By this device, textual symbols come to be associated with objects and actions familiar from other sensory channels. Could it be that the Chinese Room is like scientists puzzling over heiroglyphics before they discovered the Rosetta Stone? In _Labyrinths of Reason_, William Poundstone describes the Voynich manuscript, which is handwritten in an unknown language. Like, Codex Serafinianus, it is lavishly illustrated, yet no one can decipher the meaning of the text. Feynman, on the other hand, did decipher a codex which turned out to be an astronomical almanac. It would appear that understanding is no mean feat. --Barry Kort
rjc@aipna.ed.ac.uk (Richard Caley) (03/06/89)
In article <Mar.4.00.45.52.1989.4435@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >mike@arizona.edu (Mike Coffin) of U of Arizona CS Dept, Tucson writes: >" Why?... a computer running an >" algorithm can have properties that neither the computer (without >" algorithm) nor the algorithm (without computer) have. >I completely agree with the last proposition, except that understanding >is not one of those properties. Why? Because when Searle stands in for >the computer, doing everything it does, executing all of its algorithms, >he does not understand. Hence neither can the computer understand, when >it does exactly the same thing. So? Searle is standing in for the computer, the computer therefore does not understand. Nobody, I hope, was arguing contrary. As Mike said, the computer + the algorithm ( Searle + the rules ) may or may not understand. Searle is acting as an interpreter, I have in another window on this screen an interpreter running a screen editor - the interpreter is not an editor; the combination of interpreter and program is an editor. Substitute 'understands chinese' for 'is an editor'. -- rjc@uk.ac.ed.aipna "Politics! You can wrap it up in fancy ribbons, but you can't hide the smell" - Jack Barron
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/06/89)
geddis@polya.Stanford.EDU (Donald F. Geddis) of Stanford University wrote:
" the whole entity (Searle + memorized rules) *does* understand Chinese,
" although a section of it (Searle by himself) doesn't... Now there are
" *two* minds in Searle's brain... I don't consider the lone Searle to be an
" authority on what Searle + Memorized Rules understands, although you
" seem to. Why? [And] [a]s a matter of fact, I do [believe that I could
" fail to understand, and alpha centauri could fail to understand,
" but "I + alpha centauri" could compositely understand]
In view of what you are prepared to believe about intergalactically
distributed intelligence I am sure you will not be impressed to hear
that to this lone terrestrial neuropsychologist it seems highly
unlikely that memorizing a set of rules could give rise to two
minds in the same brain: As far as I know, only Joe Bogen's knife
has had such dramatic effects (in the "split-brain" patients -- and
possibly also early traumatic child abuse in patients suffering
from multiple personality syndome).
" The point of the [Linguistic] Turing Test [LTT] was to eliminate
" non-cognitive things [e.g., bias from appearance] from the test...
" We only want to judge cognitive ability. Whether this requires TTT
" ability is a problem for the engineers, not the judges.
I agree. But, as I argue in my paper, the LTT -- symbols-in,
symbols-out -- is systematically ambiguous about what goes on in
between input and output. It is only a CONJECTURE that symbol-crunching
alone would be enough. There are several reasons for concluding that
that conjecture is wrong, and Searle's Argument happens to be one of
them.
Ref: Harnad (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771jeff@censor.UUCP (Jeff Hunter) (03/06/89)
In article <Mar.2.23.55.02.1989.28807@elbereth.rutgers.edu>, harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > Counterargument: To ascertain (beyond reasonable doubt) that a system > CANNOT understand, you don't need a theory. Searle's argument is a case > in point: If Searle (or you, or me) does exactly what the computer does > but does not understand, then the computer does not understand. I'd like to try another thought experiment to see if I can find out why Mr Harnad and I disagree. An assumption of the Chinese room argument is that a set of rules that manipulate symbols can be built that passes the (Linguistic) Turing Test in Chinese. (ie. it can convince Chinese speakers that it too is a human Chinese speaker.) I make the further assumption that modelling a human on an atom-by-atom level would be sufficient to reproduce that human's verbal behaviour. (Gilbert Cockton will probably disagree with me on this :-), but I don't think that Steven Harnad does.) Of course to keep the simulation on track it must get the same input (from a real or simulated environment) as the real human gets. So, to start off this experiment we take Mr. Harnad into a quiet, dark room (to minimise the environmental factors), sit him in a chair, and let him get comfortable. We then take the Thought Experiment Matter Mapper (tm) and record the positions of his atoms to the precision allowed by Quantum Mechanics. We then ask "Do you understand English?" to several systems derived from this map. a) the original Mr. Harnad b) a duplicate Harnad made from new atoms in the same pattern c) a "functionally duplicate" android Harnad made using some other chemistry such as silicon molecules d) a special purpose computer hardwired into the shape of Harnad's neurons, etc e) a general purpose computer simulating Harnad's atoms moving according to the laws of physics f) an English speaker simulating e) above g) a Chinese speaker simulating e) above h) Mr. Harnad simulating e) with pencil marks on paper i) Mr. Harnad simulating e) after having memorised the entire program and database (shades of the halting problem :-) Presumably a) will answer "yes", and if the others are good simulations they will also answer "yes" as well. (To forestall the posting that there are quantum/chaos/rounding error limits to the quality of the simulation I point out that we're only running for a few (simulated) seconds, and that we can always run b) thru i) several thousand times and check for averages.) Now would Mr. Harnad be kind enough to state which of these systems really understands English (according to his definition). It seems clear that it is impossible for the humans in f) thru i) to understand the symbols they are manipulating due to sheer volume. Each would be justified in saying that they did not understand what the program thay were simulating was doing. e) thru i) are clearly only processing symbols. By my reading of Harnad's posting to date he believes they do not understand. But then, to paraphrase him, "If a computer does what Searle (or you, or me) does, but does not understand, then we do not understand". -- ___ __ __ {utzoo,lsuc}!censor!jeff (416-595-2705) / / /) / ) -- my opinions -- -/ _ -/- /- The first cup of coffee recapitulates phylogeny... (__/ (/_/ _/_ Barry Workman
bwk@mbunix.mitre.org (Barry W. Kort) (03/06/89)
In article <7431@polya.Stanford.EDU> geddis@polya.Stanford.EDU (Donald F. Geddis) writes: > In article <Mar.5.13.17.35.1989.4486@elbereth.rutgers.edu> > harnad@elbereth.rutgers.edu (Stevan Harnad) writes (in reply > to a posting of mine): > > See earlier replies on "speed and complexity." This is just > > hand-waving. It's equivalent to taking a dumb toy model and saying > > "Just more of the same will pass the TT and will have a mind." I think > > the gap is not one of speed and complexity but missing, > > yet-to-be-discovered substantive functional concepts (and not just > > symbolic ones!). > I agree that complexity arguments are not important for this thought > experiment. But it is useful to be aware that our intuitions about how > small rule sets function probably don't scale up well to large rule sets. > In no way am I claiming that this is sufficient to create intelligence; > I just don't want you to appeal to the triviality of small symbol > processing in order to claim that large symbol processing won't work either. The above passage notwithstanding, I find an interesting passage in William Poundstone's new book, _Labyrinths of Reason_, pp. 235-236: "It is conceivable that each of 100 billion neurons plays some part in actual or potential mental process. You might expect then, that the instructions for manipulating Chinese symbols as a human does would have to involve at least 100 billion distinct instructions. If there is one instruction per page, that would mean 100 billion pages. So the "book" _What to Do If They Shove Chinese Writing Under the Door_ would more realistically be something like 100 million volumes of a thousand pages each. That's approximateley a hundred times the amount of printed matter in the New York City library. This figure may be off by a few factors of 10, but it is evident that there is no way anyone could memorized the instructions. Nor could they avoid using scratch paper, or better, a massive filing system. "It's not just a matter of the algorithm *happening* to be impractically bulky. The Chinese algorithm encapsulates much of the human thought process, including a basic stock of common knowledge (such as how people act in restaurants). Can a human brain memorize something as complex as a human brain? Of course not. You cannot do it any more than you can eat something that is bigger than you are." Those readers who enjoy paradoxes such as the Chinese Room will find Poundstone's book a delightful read. --Barry Kort
arm@ihlpb.ATT.COM (Macalalad) (03/07/89)
In article <Mar.2.23.56.36.1989.28884@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >"The human," in case you've forgotten, is the only one in there, besides >the chalk and blackboards! I'll let you be the judge of how good a judge >the chalk, or Searle-plus-chalk makes... > >Look, do you think an inert book of rules is capable of understanding? >If you do, then you'll have no trouble believing that stones, chalk, >constellations and tea-leaves are capable of understanding too, and I >certainly won't be able to prove you wrong. (Animism or panpsychism -- >the belief that anything and everything can have a mind -- is the other >side of the other-minds problem.) But if we assume that we need a bit >more than that -- say, the ability to pass the LTT [sic] -- then >Searle's Argument is there to show us that that's just not good enough, >because he can pass the LTT for Chinese without understanding Chinese. >And he's all there is to the "system." It is interesting that the only point you didn't comment on was the argument that neurons seem to be the "chalk-pushers" of the brain, yet they individually don't seem to have understanding. Let's make the analogy a little more explicit. Instead of having just one person in the Chinese room, let's have a lot of people, comparable to the number of neurons in the brain. All of them are busy doing calculations on the chalkboard and passing pieces of paper around, all in strict adherence to their rulebooks. And the output, of course, is fluent Chinese. Is it so clear now which one in the Chinese room should understand Chinese? -Alex
smoliar@vaxa.isi.edu (Stephen Smoliar) (03/07/89)
In article <2498@crete.cs.glasgow.ac.uk> gilbert@cs.glasgow.ac.uk (Gilbert Cockton) writes: >In article <7645@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) writes: >Thus, I would argue that the manifestation of intelligent >>behavior cannot be observed the way we observe the size of a physical object. > >GOTCHA! OK Stephen, so what are the implications for this of a science of >Mind? Gee, Gilbert, I don't see what has gotten you so excited, unless it is a rush of triumph at the possibility that someone who devotes at least PART of his time to trying to build software models of mental processes might agree with you on something! I think your question is a good one, and I shall be curious to see if you are sympathetic to any of my answers. However, let me first state that it is not my intention to lay down a manifesto for the study of mind. Rather, I shall simply set down a few rules I am trying to live by (not always successfully); and I would encourage others to extend or modify the list. 1. If we are to engage in the study of mind, we must begin by being VERY CAREFUL in our choice of words. We are playing a game on a terrain in which intuitions can be more like land mines than landmarks. Regardless of whether or not we agree with this theories, Marvin Minsky makes a very important point in THE SOCIETY OF MIND when he illustrates the ways in which the study of mind may be misguided by confused assumptions about what is simple and what is complicated. As I remarked in an earlier article, Minsky handles the word "understand" extremely delicately in his book; and given the treatment that word has received from the likes of Searle and Harnad, I can only admire him for his caution. I am not necessarily implying that we have to deny everything and go back to COGITO ERGO SUM, but it would seem that we lack the appropriate blend of Cartesian scepticism and productive humility in our current activities. 2. Because intuitions are so dangerous here, I think it is also important that we be just as careful when we try to follow someone else's argument as we are when we try to formulate out own. I am beginning to find Stevan's games of verbal ping pong with the rest of the world tiresome to the point that they are no longer productive. He is obviously experiencing great frustration because he feels that just about everyone who is responding to his remarks does not understand him (and, of course, he KNOWS what he understands :-)). Unfortunately, the way he deals with the situation reminds me of a line from BEYOND THE FRINGE in which some proper English club types are trying to communicate with a Russian pianist: "Say it slower and louder. Then he'll understand!" Perhaps if Stevan took a bit more time to try to communicate with his opponents ON THEIR OWN CHANNEL OF COMMUNICATION, so to speak, all of us might get more out of the exchange. 3. Finally, if we are interested in the study of mind, let us not waste our time on the politics of social relations. Having seen Searle in front of an audience, I have been able to observe the man as a performer; but I try to be careful not to confuse a persuasive performance with a convincing argument. Not to pick on Searle, I would observe that I have also seen Herb Simon in action (since Jack Campin chose to respond to one of his recent abstracts); and I suspect that any audience of eager students could be as easily swayed by Simon as they could be by Searle. As with Brutus and Antony, it will boil down to who gets to say his piece last. The point is that none of this really advances our study of mind. It is simply a source of recreational ego-trips. The tragedy is that such ego-trips often determine the course of research funds; but that just demonstrates the depressing state of the world, in which the questions we try to ask are dictated by a handful of unthinking organzations with the power to dole out funds. I realize this is all highly idealistic. Probably none of us can live up to these ideals, but can we ever live up to ANY ideals? We need a lot less lecturing and a lot more questioning. Furthermore, we probably need to devote a lot more time to reading and a bit less to writing.
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (03/07/89)
From article <7431@polya.Stanford.EDU>, by geddis@polya.Stanford.EDU (Donald F. Geddis): " ... " I agree that complexity arguments are not important for this thought " experiement. ... I doubt you should agree. What kind of "non-symbolic" computations can't be modeled by symbolic ones? Those which would require too many symbols or rules, I suppose. If that is the only difficulty, complexity is an important issue. Then to argue the (in)feasibility of a life-like robot we would need to estimate the number of "distinct" brain-states that could be caused by perception, to establish at least whether it is finite. This seems to me to be the most plausible direction to pursue to salvage Harnad's arguments. Greg, lee@uhccux.uhcc.hawaii.edu
ellis@unix.SRI.COM (Michael Ellis) (03/07/89)
>> Thomas Edwards > Barry Kort >> Moreover, the incomming Chinese is also sensory input. >> Rules may exist which change due to incoming Chinese. > >Perhaps Stevan can clarify this point for us, because I believe >it is pivotal. In Searle's thought experiment, are the rules >immutable, or do they evolve as a function of the information >contained in the Chinese stories? For Searle, "the rules" may involve variables or be mutable. "The Rules" in principle may do anything a Turing machine can do or else Searle's argument loses its punch. I have heard him say as much several times. >When we talk about "understanding" in human terms, don't we really >mean the ability to gain understanding (as opposed to merely having >a fixed amount of understanding)? Sure, but neither Searle nor Harnad has overlooked that. That's just not at issue here. Go back and read your copy of Mind's_Eye again.. -michael
dan-hankins@cup.portal.com (Daniel B Hankins) (03/07/89)
In article <Mar.6.00.44.38.1989.19921@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >In view of what you are prepared to believe about intergalactically >distributed intelligence... I see distributed intelligences every day. The most common form is called a committee. Another is called a bureaucracy. >I am sure you will not be impressed to hear that to this lone terrestrial >neuropsychologist it seems highly unlikely that memorizing a set of rules >could give rise to two minds in the same brain: As far as I know, only Joe >Bogen's knife has had such dramatic effects (in the "split-brain" patients >-- and possibly also early traumatic child abuse in patients suffering >from multiple personality syndome). I must call attention to a widespread phenomenon among writers of fiction. Many authors report that the characters they invent seem to take on 'a life of their own', and that the author does not in fact know exactly what the characters are going to do or say next. However, what the author does know about the characters is their history and much of their personalities. In some sense, this knowledge comprises a program for that character, and the author's knowledge about how the world works and how people interact provides an interpreter for that character program. Some authors have even said that they do not understand why their characters do what they do, which seems to me remarkably close to what Searle is saying when he says that he does not understand Chinese. In the sense that the author can run that character's program, the author can in fact become that character. Another illustration of this is fantasy role playing games, in which the participants can be observed to exhibit (at least verbal) behavior which is *not their own*, but that of the character they have created. Again, each participant has in mind a set of rules or a program for that character's behavior, and executes that program (i.e. manipulates the symbols) during the course of play. So the claim that a person executing a set of rules is then another person is not as ridiculous as it seems on the face of things. Dan Hankins
dan-hankins@cup.portal.com (Daniel B Hankins) (03/07/89)
Here is my understanding of the external view of Searle's Chinese Room
thought experiment:
There is a room, and there are one or more native speakers of Chinese.
The native speakers write things in Chinese (questions, comments,
whatever), and pass these pieces of paper into the room. Out come other
pieces of paper with Chinese symbols on them.
All the native speakers *claim that there is a native Chinese speaker
in the room*. And to put Searle's argument to the most stringent test, we
must put no limits on how much conversation the native Chinese speaker
engages in before coming to a decision, nor must there be any limit on what
questions he can ask or conversations he can engage in, nor can there be
any limit on the number of native speakers asked to decide whether the room
contains another Chinese person.
So the native speakers claim that there is something in the room that
understands Chinese.
Here is the crucial question: *Without opening up the room to see
what is inside*, what basis do we have for disbelieving the native speakers?
The fact of the matter is, *we don't*. *Something* in there is
understanding Chinese.
It ain't Searle; so what is it?
Dan Hankinsrjc@aipna.ed.ac.uk (Richard Caley) (03/07/89)
In article <Mar.5.13.17.35.1989.4486@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >"Searle + rules" is a piece of cog-sci-fi. Are you saying that "Searle+rules" does not exist? If so your basic conception of the world seems very far from mine and, I suspect, most of the world. Most people are happy to talk about combinations of entities ( " my husband and I", " house and contents" . . . ) Now maybe they do not think that "Searle + rules" is an _interesting_ thing to talk about, and more than " three cups of coffee and a space shuttle" would be, but non the less it _is_ a thing which some strange folk might wish to discuss. >Do you believe that I >could fail to understand, and alpha centauri could fail to understand, >but "I + alpha centauri" could compositely understand? Intuativly, no. Logically, I can't say - I have no way of deciding one way or the other. Certainly "Me +alpha centauri" has properties which I do not ( eg a very high average temperature! ). I _can't_ say catagorically that "understanding" is or is not one of those properties. If anyone thinks that they can maybe they can post their proof. Similaly the "systems" argument says that Searle, by forgetting this option leaves a hole in his proof. We don't need to believe that "Searle+rules" can understand to invalidate the Chineese Room, we mearly need to see that there is no proof that this composite entity can not. >Could we >compositely feel an itch that neither of us feels singly? Can your head plus your foot feel an itch in that foot while the foot has not the equipment to feel anything, but your head has not the foot to itch with? >If you don't >PRESUPPOSE the far-fetched notion that the Chinese Room Argument set >out to debunk in the first place, then you're less inclined to come >back with it by way of a reasoned rebuttal! On the contarary, if you do not PRESUPPOSE that certain things can not "understand" the chinese room argument falls like a house of cards. -- rjc@uk.ac.ed.aipna "Politics! You can wrap it up in fancy ribbons, but you can't hide the smell" - Jack Barron
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/07/89)
jeff@censor.UUCP (Jeff Hunter) of
Bell Canada, Business Development, Toronto wrote:
" An assumption of the Chinese room argument is that a set of rules that
" manipulate symbols can be built that passes the (Linguistic) Turing
" Test in Chinese.... I make the further assumption that modelling a
" human on an atom-by-atom level would be sufficient to reproduce that
" human's verbal behaviour...
This is followed by a long list of arbitrary variations and permutations
on Searle's simple Chinese Room -- including real people, atomic
copies, synthetic copies and neural networks, as well as symbolic and
human "simulations" of all the foregoing, in unspecified languages --
none of which seem to elucidate anything. I am asked which ones can
understand English. The simple answer is that those that can pass the
TTT (including the English LTT) can. Atomic and synthetic robotic
copies could do that in principle (so what?); mere symbol-crunchers
(including symbolic simulations of atomic copies, neural nets, etc.)
cannot, for a number of reasons, among them Searle's Chinese Room
Argument.
Burying Searle's simple, straightforward point in a labyrinth of arbitrary
complications serves neither to understand it nor to refute it.
Refs: Searle, J. (1980) Minds, Brains and Programs. Behavioral and Brain
Sciences 3: 417-457
Harnad, S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771harnad@elbereth.rutgers.edu (Stevan Harnad) (03/07/89)
arm@ihlpb.ATT.COM (Macalalad) of AT&T Bell Laboratories wrote:
" the only point you didn't comment on was the argument that neurons seem
" to be the "chalk-pushers" of the brain, yet they individually don't
" seem to have understanding... Instead of having just one person
" in the Chinese room, let's have a lot of people, comparable to the
" number of neurons in the brain. All of them are busy doing calculations
" on the chalkboard and passing pieces of paper around, all in strict
" adherence to their rulebooks. And the output, of course, is fluent
" Chinese. Is it so clear now which one in the Chinese room should
" understand Chinese?
To me there is only one thing that sounds more unlikely than the notion
that the LTT could be passed by symbol-crunching alone, and that is the
notion that all neurons do is crunch symbols. But that's certainly one
way of supporting the proposition that symbol-crunchers can understand.
It's called argument by assumption (i.e., it's the same circular
reasoning we keep encountering over and over on this topic).
For the record, the only reason the real brain is immune to Searle's
Argument is that neurons are NOT just "chalk-pushers."
Refs: Searle, J. (1980) Minds, Brains and Programs. Behavioral and Brain
Sciences 3: 417-457
Harnad, S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771dave@cogsci.indiana.edu (David Chalmers) (03/07/89)
Stevan Harnad writes (many many times) [I paraphrase]: >If Searle doesn't understand, then Searle + rules can't either. >Meaningless neurons have powers that meaningless symbols do not. >Complexity is an irrelevant factor. >Symbol-crunchers are inherently, intuitively empty and stupid. >[Much else in the way of "proof by assertion".] >The "Total Turing Test" and "Robotic Functionalism" [sic] are the true answer. >Nobody out there understands these arguments, but they're right. >Maybe if I say this enough times, people will believe me. Wrong, Stevan, you lose. Can we talk about something else now? Dave Chalmers
geddis@polya.Stanford.EDU (Donald F. Geddis) (03/07/89)
In article <Mar.6.00.44.38.1989.19921@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >As far as I know, only Joe Bogen's knife >has had such dramatic effects (in the "split-brain" patients -- and >possibly also early traumatic child abuse in patients suffering >from multiple personality syndome). It is not really fair to compare the potential for two minds within Searle (after he memorizes all the rules in the Chinese Room) to current-day reality. For that, complexity arguments *are* important: the size of the rule set would be orders of magnitude beyond what a human being could potentially memorize, much less utilize effectively. So if we're going to let Searle hypothetically memorize the rules, we can't outlaw the possibility that there are now two minds in his body (the old Searle, as well as the new Searle + Rules) by looking at modern medical experiments. -- Don -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
smoliar@vaxa.isi.edu (Stephen Smoliar) (03/07/89)
In article <Mar.6.00.44.38.1989.19921@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > > >In view of what you are prepared to believe about intergalactically >distributed intelligence I am sure you will not be impressed to hear >that to this lone terrestrial neuropsychologist it seems highly >unlikely that memorizing a set of rules could give rise to two >minds in the same brain: As far as I know, only Joe Bogen's knife >has had such dramatic effects (in the "split-brain" patients -- and >possibly also early traumatic child abuse in patients suffering >from multiple personality syndome). > At least NOW we know what you are Stevan! (In an earlier article, I recall you vigorously denied being a philosopher, without saying WHAT you were. Here, I was getting ready to apply to duck test to they hypothesis that you WERE a philosopher :-).)
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/10/89)
dan-hankins@cup.portal.com (Daniel B Hankins) Portal System (TM) wrote:
" I see distributed intelligences every day. The most common form is
" called a committee. Another is called a bureaucracy.
This is not relevant. Attributing "intelligence" in such cases is either
just an analogy or a figure of speech. Can a committee feel pain? If
not, then it can't understand either.
" I must call attention to a widespread phenomenon among writers of
" fiction.... Many authors report that the characters they invent seem to
" take on 'a life of their own'...
Irrelevant again. That author's have minds is not in doubt. The sources
of literary creativity or social judgment are not at issue either.
And certainly the minds of fictitious characters are as fictitious as
the characters themselves.
" All the native speakers [who are administering the Lingustic Turing
" Test (LTT)] *claim that there is a native Chinese speaker in the
" room*... *Without opening up the room to see what is inside*, what
" basis do we have for disbelieving the native speakers? The fact of the
" matter is, *we don't*. *Something* in there is understanding Chinese.
" It ain't Searle; so what is it?
All you are doing here is restating the premise of the LTT. Searle's
Argument shows what untoward conclusions arise from accepting the
premise that the LTT could be successfully passed by symbol-crunching
alone. Sometimes the best way to deal with an untoward conclusion
is to revise your premises. The people who are arguing till they are
black and blue that "rules understand" or "chalk understands" or
"Searle's brain has another mind that understands" would do better
to stop straining at it and simply confront the possibility that
it is not possible to pass the LTT by symbol crunching alone!
By the way, although the constraint ends up doing spurious double duty,
the reason Turing formulated the TT as the LTT rather than the Total
(robotic) Turing Test (TTT) was not explicitly because (1) he was
endorsing the symbol-crunching theory of mind, but because (2) he
didn't want anyone to be biassed by the APPEARANCE of the candidate. In
these Star-Wars days of loveable tin heroes, we perhaps no longer need
to be so worried that robots will be denied the benefit of the doubt
just because of their LOOKS. So let us consider the possibility that
to pass the LTT, a candidate may need the functional wherewithal to pass
the TTT, and that that functional wherewithal will not be mere
symbol-crunching.
Refs: Harnad, S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771geddis@polya.Stanford.EDU (Donald F. Geddis) (03/10/89)
In article <Mar.9.12.22.06.1989.21547@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >Sometimes the best way to deal with an untoward conclusion >is to revise your premises. The people who are arguing till they are >black and blue that "rules understand" or "chalk understands" or >"Searle's brain has another mind that understands" would do better >to stop straining at it and simply confront the possibility that >it is not possible to pass the LTT by symbol crunching alone! We start with a hypothesis, that "mere symbol crunching" has the capability to pass the LTT. From that you are quite correct: if we logically derive a conclusion that everyone agrees is absurd, then (by reductio ad absurdum) we would have shown that the premise is false. But so far you seem to be the only one who view the System Reply conclusion (that the Searle + Rules combination is a mind that understands) as an absurd conclusion. It isn't good enough for your argument that the absurdity is obvious to you; it must be obvious to everyone else as well (such as: 0=1). The truth is that in this case the conclusion is perfectly consistent with the original hypothesis, so Searle's argument shows nothing. Which isn't quite the same as actually proving that symbol processing *could* achieve intelligence, but it is much better than the devastating blow you seem to be claiming. -- Don Geddis -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
mike@arizona.edu (Mike Coffin) (03/10/89)
Stevan Harnad writes, in part > All you are doing here is restating the premise of the LTT. Searle's > Argument shows what untoward conclusions arise from accepting the > premise that the LTT could be successfully passed by symbol-crunching > alone. Sometimes the best way to deal with an untoward conclusion > is to revise your premises. The people who are arguing till they are > black and blue that "rules understand" or "chalk understands" or > "Searle's brain has another mind that understands" would do better > to stop straining at it and simply confront the possibility that > it is not possible to pass the LTT by symbol crunching alone! I think you misunderstand our state of mind. ;-) You seem to think that, realizing our position well-nigh untenable, we are desperately inventing ever-more-bizarre rationalizations for our preconceived ideas. Of course, I can't speak for others, but I am not "straining" in the slightest. I see no untoward, or even unexpected, conclusion! The systems reply seems the most natural thing in the world to me --- and I don't even have a Yale education. Life is absolutely FULL of situations where large aggregates of simple objects don't act simply. It is the most natural thing in the world to expect the whole to be greater than the sum of the parts. It is "common sense." In fact, it would be surprising if a large aggregate didn't have "a life of its own." I learned very early --- probably while watching my father take apart, clean, and reassemble clocks and watches --- that if you take apart complicated things you expect to find simpler things, and if you put a lot of simple things together, you get complicated things. Playing with tinker-toys, erector sets, microscopes, physics, and computers all reinforced this sense. Am I alone in this sense that the whole is generally greater than the sum of its parts? -- Mike Coffin mike@arizona.edu Univ. of Ariz. Dept. of Comp. Sci. {allegra,cmcl2}!arizona!mike Tucson, AZ 85721 (602)621-2858
ins_atge@jhunix.HCF.JHU.EDU (Thomas G Edwards) (03/10/89)
In article <Mar.6.23.26.26.1989.5039@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >arm@ihlpb.ATT.COM (Macalalad) of AT&T Bell Laboratories wrote: >" the only point you didn't comment on was the argument that neurons seem >" to be the "chalk-pushers" of the brain, yet they individually don't >" seem to have understanding... Instead of having just one person >" in the Chinese room, let's have a lot of people, comparable to the >" number of neurons in the brain. All of them are busy doing calculations >" on the chalkboard and passing pieces of paper around, all in strict >" adherence to their rulebooks. >To me there is only one thing that sounds more unlikely than the notion >that the LTT could be passed by symbol-crunching alone, and that is the >notion that all neurons do is crunch symbols. But that's certainly one >way of supporting the proposition that symbol-crunchers can understand. >It's called argument by assumption (i.e., it's the same circular >reasoning we keep encountering over and over on this topic). >For the record, the only reason the real brain is immune to Searle's >Argument is that neurons are NOT just "chalk-pushers." Upon what evidence do you base your statement "neurons are NOT just 'chalk pushers.'"? I'll be the first to admit that neurons do have a complicated transfer function between input and output, but your statement gives them a little more cognitive ability than I'm ready to accept. Creatures with relatively few neurons show little cognitive ability (Aplysia for instance). Or perhaps our definitions of chalk-pushers is a little different. I assume that by "chalk-pusher" you mean someone with memory and a releatively simple transfer function between input and output (perhaps a little more complicated than 1/(1+e^(-x)), but nethertheless much less complicated than that of any relatively lucid [in terms of being able to deal with real world problems] brain, including Aplysia, grasshoppers, etc.) From my desperate attempts to find neural net literature five years ago, I know there are hoards of books desribing mathematical models of real neurons (probably not including neuropharmacology, which _is_ important, but including nerual potential values). Anyway, the main idea here is that neurons are not homonclei!. They cannot do any kind of reasonable cognitive task without being in a weighted network with many, many others. The neruon does not understand, the network _does_ (unless you are ready to drop the concept that people understand). Is this not a good precedent to show that systems do exist in which the parts do not understand, yet the system does? Furthermore, on this ever "angel on the head of a pin" debate, I believe that the subjective concept of understanding is not scientifically provable as per the non-performance oriented concept. If something is in a opaque box, how can we know if it understands or not? It could just as well be a cat, cow, rock, or person. If we think we can determine whether the mind understands or not while we keep it in a box, we are deluding ourselves. A performance test based on input and output which shows real-world reasoning is the best we can ever hope for. -Thomas Edwards ins_atge@jhunix
jeff@censor.UUCP (Jeff Hunter) (03/10/89)
... harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > [me condensed. assume an atom-by-atom model of a human is sufficient rules > to reproduce linguistic behaviour. now "record" atoms of a real human.] > > This is followed by a long list of arbitrary variations and permutations > on Searle's simple Chinese Room -- including real people, atomic > copies, synthetic copies and neural networks, as well as symbolic and > human "simulations" of all the foregoing, in unspecified languages -- > none of which seem to elucidate anything. I'm sorry if the examples seemed arbitrary. I was listing some alternative "copies"of the original human, from flesh-and-blood to a purely mental simulation. I was unsure where you would draw the line and say that understanding ceased. > I am asked which ones can > understand English. The simple answer is that those that can pass the > TTT (including the English LTT) can. Atomic and synthetic robotic > copies could do that in principle (so what?); mere symbol-crunchers > (including symbolic simulations of atomic copies, neural nets, etc.) > cannot, for a number of reasons, among them Searle's Chinese Room > Argument. A clear answer. Thank you. I went back and re-read your un-expired articles here. Let me try my understanding (that word again) of your position. "A purely symbolic simulation is, by definition, not real. A system which has (at least some) real parts is immune to Searl's Chinese Room argument, and thus can potentially understand. A system which can pass the Total Turing Test (simulate a real human) can probably understand." Please correct me if I've mis-stated your opinions. I'm curious as to the bounds you put on the TTT. Does a candidate have to look exactly human even under X-rays, etc... or does it just have to be able to pass the LTT, look vaguely humanoid, and be able to pick up a glass? An interesting property of any of my "symbolic simulations of atomic copies" is that it is possible, in principle, to reconstitute a living human from the symbolic information of the position of the atoms. This new human seems as good a candidate to pass the TTT as any random man on the street, and so can "understand" with the best of them. (You may at this point say "of course, so what?". Please don't get annoyed. I'm just trying to fathom your concept of understanding, which I find strangely counter-intuitive.) Do you agree that a re-embodied simulation can understand? Now let us take a non-Chinese-speaking human, and record her. She goes in a sealed room, with only an optical fibre link to the rest of the world. (Note: purely symbols in, symbols out.) Her simulation is put in a similar (but simulated) room. Both of them are taught Chinese (by correspondence, telephone, video, etc) until the real human understands Chinese, and the simulated one has simulated understanding. To an external observer they should be as alike as twins. There is no way that I can see to distinguish which is real without opening the room (or probing it with cosmic rays). (Remember this is a thought experiment with an arbitrarily good simulation at atomic level.) Now open the real room and let the volunteer out. Reconstitute the simulated room, open it, and let the second copy of the volunteer out. Presumably both can pass the TTT. Each will state that they understood Chinese while they were in the room, so the introspective "I know when I understand something as opposed to just manipulating meaningless symbols" property of understanding seems to be common to both real and simulated humans. I can't see any functional difference, inside or out, between the real and simulated understanding. Do you see any difference aside from the fact that the simulated one is purely non-physical? Next thought experiment: take a human. record the brain, then remove it (and store it, who knows when a spare brain will come in handy :-). add hardware to each nerve to record incoming signals, send outgoing ones, and mask the truncation of the nerve. add more hardware to remove glucose from incoming blood, etc.. add a room containing a miniaturized ultra-quick Searl running an atomic level simulation of the recorded brain. The hardware communicates signals with Searl using some real actuator (a series of laser pulses perhaps). The result would seem to be a human, and should be able to pass the TTT. Do you agree? Oh it wouldn't get concussions due to brain bruises. Add a few acceleration sensors. We're back in business.) Now if the original human spoke Chinese we have: Searle does not understand Chinese. You repeatedly ridicule the notion that "Searle + rules" can understand Chinese. "Searl + rules + laser" and "Searl + rules + laser + interface hardware" might or might not understand (I don't know where you stand on this). "Searl + rules + laser + interface hardware + body" can pass the TTT, and therefore you should believe that this can understand. Do you? I find it hard to believe that adding a few peripherals to the processor (I'm a programmer don't cha know :-) magically adds understanding somehow. Please try to explain again. Thanks. > > Burying Searle's simple, straightforward point in a labyrinth of arbitrary > complications serves neither to understand it nor to refute it. > Well it's so simple that dozens of messages later there still is no clear agreement on what you see as the difference between real and simulated understanding. I'm hoping to accelerate the process a bit. .... keep smiling ... -- ___ __ __ {utzoo,lsuc}!censor!jeff (416-595-2705) / / /) / ) -- my opinions -- -/ _ -/- /- No one born with a mouth and a need is innocent. (__/ (/_/ _/_ Greg Bear
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (03/10/89)
In article <52507@yale-celray.yale.UUCP> engelson@cs.yale.edu (Sean Engelson) writes: >But a physicist can give me a simple and effective procedure by which >I can measure the charge of a body, or the force of gravity. I have >seen no such procedure of criterion for recognising understanding, >other than I/O equivalence with that which we call understanding in >humans. Under that criterion, the Chinese Room understands. You have seen .... Have you looked? "Verstehen" lies at the heart of hermeneutics and several other intellectual traditions. Unfortunately, you come across as a naive positivist, so I doubt whether you would get anything from Dilthey, later hermeneutics, the Frankfurt School, phenomenology, Malinowski, ethnomethodology or social action theory (to start near to home and thus in your own language). I/O equivalence is the sense-data argument, you're nearly 60 years behind the times. This got taken to its extreme and fell apart in the 1930s with some of the Vienna crowd. Wittgenstein is an easy place to start too. Have a look at his notion of family resemblance (for games, chairs etc.). You'll see that many of the meanings which you take for granted aren't as hard as you'd want them to be. I believe that some ongoing physics experiments in Nevada/near also are casting doubts on our ideas about gravity too. Physicsis getting a lot looser than it used to be, just look at how long physicists will argue over a cat in a box. Hardly good practical empirical experiment like you brave AI boys. Understanding is attributed during practice. Perhaps a TTT could pass it, but I doubt it, as no-one's going to get enough encoded to simulate anything near the common sense repetoire of humans. Finally, the TTT cannot be like the LTT, in the missionary position and one to one. The real TTT's going to have to be public, communal and involve more than one task. I can't see why anyone is bothered about believing whether this is possible "in theory" as there is as yet no possible theory in which it could be true. -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
smoliar@vaxa.isi.edu (Stephen Smoliar) (03/10/89)
In article <Mar.9.12.22.06.1989.21547@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > > >dan-hankins@cup.portal.com (Daniel B Hankins) Portal System (TM) wrote: > >" I see distributed intelligences every day. The most common form is >" called a committee. Another is called a bureaucracy. > >This is not relevant. Attributing "intelligence" in such cases is either >just an analogy or a figure of speech. Can a committee feel pain? If >not, then it can't understand either. > I see we're back to playing fast and loose with language (specifically words like "intelligence" and "understand") again. Any well-coordinated military seem (such as, for example, a tank crew) should be so closely knit that to call the union of that team an organic being is no mere metaphor. AS A TEAM, they will respond to stimuli of positive and negative reinforcement of their actions; and there is no reason why an outside observer would not say that the team is basically seeking pleasure and avoiding pain. It seems that Stevan's argument boils down to the assumption that certain words and phrases (such as "understand" and "feel pain") are ONLY applicable to humans. Stevan is certainly entitled to that assumption, but there seem to be enough of us willing to question it that he cannot try to promote it from "assumption" to "universal truth."
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (03/10/89)
In article <9560@megaron.arizona.edu> mike@arizona.edu (Mike Coffin) writes: > You do this in spite of all the >evidence of your senses --- remember, this system passes the Turing >test! You have this impressive system in front of you; it >certainly seems to understand Chinese; Searle certainly doesn't; the >rules by themselves certainly don't. Yet you ignore the evidence and >insist on talking about components of the system as if they were the >system. It almost looks like you're in the grips of an ideology :-) The system passes the LTT (because Searle so defines the gedanken experiment), but it DOES NOT understand - certainly not in the sense of the way people use the word. So, what is AI? An attempt to build artefacts, or an attempt to brain wash us into seeing 5 when 4 fingers are held up? Stop messing with my language - 200 years of melting pot have wrecked it enough already :-( Everyone is in the grip of some ideology, but the systems' one is just plain silly if it attributes "understanding" to a system. I am a holist, but I don't see how an attribute of a part can be transferred to the whole if it doesn't exist in the part. The interesting thing about systems is the attributes of the whole which CANNOT be attributes of the parts, not true here I'm afraid. -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
staff_bob@gsbacd.uchicago.edu (03/11/89)
In article <18073@iuvax.cs.indiana.edu>, dave@cogsci.indiana.edu (David Chalmers) writes... >Answer me these questions. > (1) Do you believe neurons (taken alone) have semantics. > [I take it the answer has to be "No."] > (2) Do you believe the brain as a whole has semantics. > [I take it the answer is "Yes."] > >Given this, you must accept that semantics can arise out of non-semantic >objects. Most of us are a little baffled as to how. It seems that the >only half-way reasonable tack we can take to answer this question is to >say that what is important for semantics (and the subjective in general) >is not so much those objects as the complex patterns that they form. > > [much deleted] > > Dave Chalmers > Center for Research on Concepts and Cognition > Indiana University The term 'semantics' comes out of linguistics, and is not a synonym for the more general term, 'meaning'. One cannot discuss semantics outside of the context of a language. For a given, well-formed expression in any language, the semantics of that expression is what it is intended to signify. Thus, generally, we can say that the semantics of a sentence is its meaning. I don't know exactly what Mr.Chalmers is trying to say in this passage. Are we to take a neuron as a well formed sentence in some language that is nonetheless devoid of meaning? In the context of formal language theory, neurons do have well defined semantics. We think we know how single neurons work: for a given set of input values, there is a well defined output. If I remember correctly, it is possible to characterize these actions with regular expressions. Therefore, I would have to say that the answer to [1] is "Yes". Mr.Chalmers argument follows from his premise. He assumes that semantics means "something more complex" than simple input/output operations, and his conclusion emerges directly from this (questionable) assumption. Anyone who has studied compiler writing in general or denotational semantics in particular is familiar with semantics in the low level sense, but Mr. Chalmers discludes this usage, either by choice or through ignorance of the use and meaning of the word 'semantics'. He then goes on to prove that since he has assumed no low level semantics, but has assumed high level semantics, that semantics must emerge somewhere in the middle. To excuse the misuse of the word "semantics", let us substitute some other, more general term, such as meaning (or perhaps the U-word, understanding). Then I would have to say that the answer to [2] is no. It is certainly possible to claim that meaning does not exist in the brain, it exists in the mind. I'm sure that many readers will object to the distinction, and I do not care to defend it, but my point is this: the Mind/Body problem has never been solved, and it may well be insoluble. We observe that something called Mind exists ("I think, therefore I am" is a proof for the existence of Mind), and we also observe that Minds coexist with bodies. As Mr.Chalmers asserts, most of us are baffled as to how. The general assumption these days is that Mind is a by-product of a body, but a recent posting has made the valid point that we cannot show that a body is not a by-product of Mind. In any event, I think that one can show many more than half-way reasonable tacks to take in approaching this problem than Mr.Chalmers has suggested. I need only list all of the great philosophers from Plato and Aristotle through DesCartes, Locke, Hume, Kant, Hegel, Schopenhauer, Heidegger and Sartre to begin to enumerate them. A lot of people have grappled with this question, none to the general satisfaction of the rest of humanity. The recent debate in this news group in re Searle's Chinese Room thought experiment hinges on the Mind/Body question. Is not the premise of Searles argument just that understanding only occurs in Mind, and Mind exists neither in the system (Searle+rules) nor in a computer? IMHO, thia entire debate has revolved around these two assertions, neither of which can be proven or disproven. It interests me that so many people of scientific bent show an absolute distaste for philosophy, yet somehow feel themselves qualified to discourse at length on the greatest philosophical questions of the ages. I' reminded of a anecdote from the book "The Dreams of Reason" by Heinz Pagel, who in his capacity (I believe) as executive director of the New York Academy of Science once arranged a talk to be given by the Dali Lama. In the subsequent question and answer session, someone tried to ask the Dali Lama where intelligent machines fit into his philosophy/ religion/system. The Dali Lama merely responded, "When you have such a machine, here, in front of us, then I will answer your question." What can possibly be gained from this debate over Searle's thought experiment? Assuming that we could come to some sort of universal agreement about this (and I really don't think that is possible) will it make a single iota of difference to the work we're doing? Is this not really a theological debate, more than anything else? That is to say, aren't the arguments we have seen to this point really defenses of various faiths in the possiblilty of machine 'awareness'? Can't we let that debate wait until we're a little bit closer to something called machine intelligence? R.Kohout
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/11/89)
In article <28207@sri-unix.SRI.COM> ellis@unix.sri.com (Michael Ellis) writes: >> Jeff Dalton >> David Sher >>>Does anyone believe that they can build a machine with a soul? It is >>>just as easy to build in Searle's "understanding." >>It's certainly true that it's hard to see what could ever convince >>Searle that anything had understanding. > Then you missed something. Searle is *already convinced* that at least: > 1. Searle has it > 2. Other humans have it Sure, but that's not because he used to think otherwise and someone convinced him he was wrong. Perhaps I should have added "unless the thing uses brains or green slime". Anyway, you haven't said anything about how Searle might be convinced, only that he is *already convinced*. So if I missed something, it must be something else. Consider an example. Searle talks about the "causal powers of the brain". He thinks there's *something* about brains that results in understanding. But he doesn't say anything about what it is. Well, that's reasonable, because we don't know all that much. But the causal powers end up being something we infer from the understanding and not much help as a way to show that something has understanding in the first place. All of this is fine, but in the end it's not clear what might show that green slime, for example, might have the right sort of causal powers.
dave@hotlr.ATT ( C D Druitt hotlk) (03/11/89)
In article <15469@cup.portal.com> dan-hankins@cup.portal.com (Daniel B Hankins) writes: > In article <Mar.6.00.44.38.1989.19921@elbereth.rutgers.edu> > harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > > >In view of what you are prepared to believe about intergalactically > >distributed intelligence... > > Some authors have even said that they do not understand why their > characters do what they do, which seems to me remarkably close to what > Searle is saying when he says that he does not understand Chinese. > > the character they have created. Again, each participant has in mind a set > of rules or a program for that character's behavior, and executes that > program (i.e. manipulates the symbols) during the course of play. > > So the claim that a person executing a set of rules is then another > person is not as ridiculous as it seems on the face of things. > > > Dan Hankins Anybody tried Tim Leary's "Mind Mirrors" ? In order to play, you have to react to various scenarios as a character chosen and composed for you would react. In order to win, you have to focus your choice of reactions through Tim Leary's mind (e.g. understand his set of rules for character behaviour). This is similar to a musician's concept of "putting his finger through his guitar, out through the PA, into the audiences' mind" and saying something symbolically that can be understood even in Chinese. Point is, there are some things we all have in common. In some ways, we are all different. Experiences have something to do with shaping both aspects. If you can see how these terse generalizations apply to this newsgroup, there is hope for AI in general. If you want an extended explanation, just let me know. Dave Druitt (the NODES) (201) 949-5898 (w) (201) 571-4391 (h)
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/11/89)
staff_bob@gsbacd.uchicago.edu (R.Kohout) of
University of Chicago Graduate School of Business asks:
" What can possibly be gained from this debate over Searle's thought
" experiment? Assuming that we could come to some sort of universal
" agreement about this (and I really don't think that is possible) will
" it make a single iota of difference to the work we're doing?
The historian J. H. Hexter once wrote:
in an academic generation a little overaddicted to "politesse," it
may be worth saying that violent destruction is not necessarily
worthless and futile. Even though it leaves doubt about the right
road for London, it helps if someone rips up, however violently, a
`To London' sign on the Dover cliffs pointing south...
Searle's Argument has helped to show that pure symbol-crunching is not
the right road to the mind. In my JETAI paper I gave more reasons, and
in my book I try to show another road, a bottom-up one, in which
symbolic representations are grounded nonmodularly in nonsymbolic
representations.
Refs: Searle, J. (1980) Minds, Brains and Programs. Behavioral and Brain
Sciences 3: 417-457
Harnad, S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
Harnad, S. (1987) Categorical Perception: The Groundwork of Cognition.
Cambridge University Press.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771dave@cogsci.indiana.edu (David Chalmers) (03/11/89)
Just very briefly. I don't want to drag this discussion out even longer... In article <2233@tank.uchicago.edu> staff_bob@gsbacd.uchicago.edu writes: >In article <18073@iuvax.cs.indiana.edu>, dave@cogsci.indiana.edu (David Chalmers) writes... > >>Answer me these questions. >> (1) Do you believe neurons (taken alone) have semantics. >> [I take it the answer has to be "No."] >> (2) Do you believe the brain as a whole has semantics. >> [I take it the answer is "Yes."] >> >The term 'semantics' comes out of linguistics, and is not a synonym >for the more general term, 'meaning'. One cannot discuss semantics outside >of the context of a language. For a given, well-formed expression in any >language, the semantics of that expression is what it is intended to signify. >Thus, generally, we can say that the semantics of a sentence is its meaning. Sorry, I wasn't using the term "semantics" in its linguistic sense. I was using it in the more general sense of "meaning" or "representational richness" or whatever that weird thing is that goes on in a human mind. This is the sense in which the word is used by Searle (and quite a few others, incidentally). I'm sorry if it confused you. >To excuse the misuse of the word "semantics", let us substitute some other, >more general term, such as meaning (or perhaps the U-word, understanding). >Then I would have to say that the answer to [2] is no. It is certainly possible >to claim that meaning does not exist in the brain, it exists in the mind. Well, if you like. But most of us believe that minds are heavily dependent on brains for their existence. So whether it is the brain or the mind which supports meaning (and I'm tempted to say that it's only a "semantic" question), nevertheless the existence of a brain seems sufficient to produce minds and thus meaning (or whatever that word is). >A lot of people have grappled with this question, none to the general >satisfaction of the rest of humanity. The recent debate in this news >group in re Searle's Chinese Room thought experiment hinges on the >Mind/Body question. Is not the premise of Searles argument just that >understanding only occurs in Mind, and Mind exists neither in the system >(Searle+rules) nor in a computer? IMHO, thia entire debate has revolved around >these two assertions, neither of which can be proven or disproven. I agree (mostly). Searle's Chinese Room is only a mystery in that the Mind- Body problem is also a mystery. The whole question is: how can something as strange as a mind emerge from a mere physical system? Despite 2000+ years work, still nobody can answer this satisfactorily, though I like to think that people are getting closer. (Surely we have made some advances on Descartes' dualism, for instance?) I believe that late 20th century abstract functionalism is the first theory which has even a chance of being correct, although it still has a lot of problems. A discussion of the more general issues of the Mind/Body problem might be fun, incidentally, independent of the thrashed-to-death rehashing of Searle. >What can possibly be gained from this debate over Searle's thought experiment? >Assuming that we could come to some sort of universal agreement about >this (and I really don't think that is possible) will it make a single >iota of difference to the work we're doing? Is this not really a theological >debate, more than anything else? That is to say, aren't the arguments >we have seen to this point really defenses of various faiths in the >possiblilty of machine 'awareness'? Can't we let that debate wait until >we're a little bit closer to something called machine intelligence? What? And put us philosophers out of a job? Dave Chalmers (dave@cogsci.indiana.edu)
geddis@polya.Stanford.EDU (Donald F. Geddis) (03/11/89)
In article <2233@tank.uchicago.edu> staff_bob@gsbacd.uchicago.edu writes: >What can possibly be gained from this debate over Searle's thought experiment? >Can't we let that debate wait until >we're a little bit closer to something called machine intelligence? > R.Kohout Not quite. If the Turing Test model of understanding, thinking, and intelligence is accurate, then we must apply behavioral criteria to a system to tell whether it does cognition. And in that case, some current systems are uncomfortably close (for humanist critics) to already thinking. Eliza does a reasonable job at a very small (and cleverly chosen...) domain. More realistically, some large expert systems give as good answers to typical questions in their domains as human experts do. Of course you could always say that "real" understanding requires ability in all areas of human existence, not just some narrow field. But then my mother doesn't understand theoretical physics. It's a spectrum of possibilities, and we're all somewhere on there. AI systems tend to clutter the low end, but there's no sharp dividing line where version (n) isn't intelligent, but version (n+1) is. -- Don -- Geddis@Polya.Stanford.Edu "We don't need no education. We don't need no thought control." - Pink Floyd
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/11/89)
jeff@censor.UUCP (Jeff Hunter)
of Bell Canada, Business Development, Toronto wrote:
" I'm curious as to the bounds you put on the TTT. Does a candidate have
" to look exactly human even under X-rays, etc... or does it just have to
" be able to pass the LTT, look vaguely humanoid, and be able to pick up
" a glass?
The TTT requires that a candidate be able to DO everything a human can
do. It must be indistinguishable from a person in its behavioral capacity.
How it LOOKS does not matter in principle (though it might in practice
bias a human judge -- that was the motivation [not just an over-riding
faith in the functional sufficiency of pure symbol-crunching] for
Turing's "out-of-sight/into-mind" constraint, leading to the LTT
in preference to the TTT).
Both physical appearance and observable details of the physical structure
and function of our bodies (including our brains) are irrelevant
to our informal, intuitive, everyday solutions to the other-minds
problem; I also think they will turn out to be just fine-tuning
variables in the construction of a successful TTT-passing model. Most
of the real problems will have been solved before we get around to the
last bit of fine-tuning. (This is not to imply that brain function
may not give mind-modelers some functional clues.)
" it is possible, in principle, to reconstitute a living human from the
" symbolic information of the position of the atoms... Do you agree
" that a re-embodied simulation can understand?
Of course I do. I have even agreed that a simulation of a plane or a
mind can symbolically encode (and aid us in discovering and testing)
ALL of the relevant causal and functional principles of flying and
understanding, respectively, that need to be known in order to
successfully implement a real plane that flies and a real mind that
understands. I simply deny that the simulation flies or understands.
Now in the case of flying it's perfectly obvious why symbol-crunching
alone will never get you off the ground; but because of (1) the power
of Turing Machines and natural language as well as (2) the inherent
ambiguity of the LTT (symbols-in/symbols-out) on this question, some of
us seem to have made the mistake of thinking that in the case of the
mind the simulational medium and the implementational medium can be the
SAME: mere symbol-crunching. Searle's arguments and my own are intended
to show that this is incorrect. (The rest of your list of hypothetical
examples is again irrelevant.)
" You repeatedly ridicule the notion that "Searle + rules" can understand
" Chinese... [but] "Searle + rules + laser + interface hardware + body" can
" pass the TTT, and therefore you should believe that this can
" understand. Do you? I find it hard to believe that adding a few
" peripherals to the processor... magically adds understanding somehow.
" Please try to explain again.
I too find it hard to believe that adding on peripherals to a symbol-cruncher
will make it magically understand -- in fact I give reasons why this
won't even make it magically pass the TTT. It takes more (I never tire
of saying, and my interlocutors never tire of ignoring) to ground
symbols than simply hooking peripherals onto a symbol-cruncher.
" Well [if Searle's Argument is] so simple that dozens of messages later
" there still is no clear agreement on what you see as the difference
" between real and simulated understanding...
I have to remind you that the actual number of opponents I've had in
this discussion is rather small relative to the size of the readership
of the Net (in fact it's often the same individuals coming back round
after round); and their repertoire of arguments is even smaller. Not
that I think I would win if a poll were conducted (even if opinion
polls were a rational way to decide such matters); after all, on
"comp.ai" a critic of symbol-crunching is not exactly preaching to the
converted...
Refs: Searle, J. (1980) Minds, Brains and Programs. Behavioral and Brain
Sciences 3: 417-457
Harnad, S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771newsuser@LTH.Se (LTH network news server) (03/13/89)
In article <Mar.11.00.17.25.1989.4801@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >Searle's Argument has helped to show that pure symbol-crunching is not >the right road to the mind. In my JETAI paper I gave more reasons, and >in my book I try to show another road, a bottom-up one, in which >symbolic representations are grounded nonmodularly in nonsymbolic >representations. I for one think you haven't been able to actually show anything. But please go ahead and show by doing, and maybe the futile fight with words will eventually be decided by someone writing a program, building a robot, or something, and not just trying to prove that other people's approaches are wrong, and :-) failing to do so. -- Jan Eric Larsson JanEric@Control.LTH.Se +46 46 108795 Department of Automatic Control Lund Institute of Technology "We watched the thermocouples dance to the Box 118, S-221 00 LUND, Sweden spirited tunes of a high frequency band."
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (03/13/89)
In article <7698@venera.isi.edu> smoliar@vaxa.isi.edu.UUCP (Stephen Smoliar) writes: >Gee, Gilbert, I don't see what has gotten you so excited, unless it is a rush >of triumph at the possibility that someone who devotes at least PART of his >time to trying to build software models of mental processes might agree with >you on something! I think your question is a good one, and I shall be curious >to see if you are sympathetic to any of my answers. However, let me first >state that it is not my intention to lay down a manifesto for the study of >mind. Gee Stephen, you forgotten your smiley. I'd like to see the manifesto, rather than a limp restatement of Bacon's dislike of the "idols of the market" in the shape of the intuitions resplendant in our language. I'm all for scepticism about meanings carried in public language, but this scepticism should apply equally to the products of AI, but it's all hope, "don't smother the budding flower" and "astronomy took centuries" there. All I can say from your account of scholarship and intuition is that it smacks of hypocrisy: the products of AI come in for far less searching scepticism than the everyday intuitions in our language (and as we don't speak the same dialects of English, I don't know if our common sense understandings are shared). If you know what you're on about, if you know how you judge progress in AI, if you know what marks out a good AI research proposal from a poor one, then you should share it with us. You are doing AI, so tell us how you do it, what it tells us, and why we should believe you. Otherwise it's 0/10 for scholarship I'm afraid. Cruel, but there are always jobs at the bank :-) (lots of them). -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
gilbert@cs.glasgow.ac.uk (Gilbert Cockton) (03/13/89)
In article <Mar.11.00.17.25.1989.4801@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >The historian J. H. Hexter once wrote: > > in an academic generation a little overaddicted to "politesse," it > may be worth saying that violent destruction is not necessarily > worthless and futile. Even though it leaves doubt about the right > road for London, it helps if someone rips up, however violently, a > `To London' sign on the Dover cliffs pointing south... > Thanks for broadening things out again. For those who missed it, my first trade was history, though Hexter's comments never seemed to apply to British history, where demolition of the shoddy has always been the order of the day. Hexter is a good humanist source for sensible perspectives on matters of mind. In his "History Primer", he discusses three explanations of a "muddy pants" episode. Needless to say, the really dumb one reads like a reasoning trace (an explanation? - hah!) from an expert system. The preferable explanation, which is perfectly adequate for *UNDERSTANDING* is more cogent and less fussy. The common sense context of human understanding rules out a rule-based approach. No-one in AI is up to encoding it, and no-one could maintain it. I'd like to define understanding as the ability to integrate relevant knowledge with any current context. For many tasks, it is impossible to see how a machine could even pass a LTT. AIers cannot program what they do not understand. AIers understand very little. -- Gilbert Cockton, Department of Computing Science, The University, Glasgow gilbert@uk.ac.glasgow.cs <europe>!ukc!glasgow!gilbert
ins_atge@jhunix.HCF.JHU.EDU (Thomas G Edwards) (03/16/89)
In article <2568@crete.cs.glasgow.ac.uk> gilbert@cs.glasgow.ac.uk (Gilbert Cockton) writes: >The system passes the LTT (because Searle so defines the gedanken >experiment), but it DOES NOT understand - certainly not in the sense of >the way people use the word. It appears that "people" cannot use the word "understand" to refer to cognitive associations of computers, only people, and occasionally animals. Despite popular usage, there is no reason to expect artifacts not to be able to do what we consider "understanding" in humans. But until we ourselves define what "understanding" is, which the discussion on this group have failed to come to a conclusion upon, we cannot prove anything concerning artifactual understanding. >Everyone is in the grip of some ideology, but the systems' one is just >plain silly if it attributes "understanding" to a system. I am a >holist, but I don't see how an attribute of a part can be transferred >to the whole if it doesn't exist in the part. You say you cannot understand how an attribute of a part can be transfered to the whole if it doesn't exist in the part. This is reasonable. However, an attribute of _parts_ can be transfered to a whole if it doesn't exist in any singular _part_. (i.e. summing a+b+c+d can be accomplished by a system of three parts, one which sums a+b, another which sums c+d, and a third which sums the output of the first two parts). > The interesting thing >about systems is the attributes of the whole which CANNOT be attributes >of the parts, not true here I'm afraid. You are saying the attributes of the whole CAN be the attributes of the parts here...I am not sure I understand your concept here, but if we assume you mean "here" to refer to "cognition" then you say that the parts of cognition are capable of cognition, the parts of understanding understand. If we assume the human body to be made up of parts (atoms and electrons), from the above assumption, we are assuming that (atoms and electons) can understand. The conclusion I'd like to draw is that systems _typically_ have attributes which one would find very, very difficult to imply from examining each part. (examples...any dynamic system: Julia Sets, turbulence in air or fluids, time between faucet drips, etc.) -Thomas Edwards
smoliar@vaxa.isi.edu (Stephen Smoliar) (03/16/89)
In article <2573@crete.cs.glasgow.ac.uk> gilbert@cs.glasgow.ac.uk (Gilbert Cockton) writes: > I'm all for scepticism about meanings carried in public >language, but this scepticism should apply equally to the products of >AI, but it's all hope, "don't smother the budding flower" and "astronomy >took centuries" there. All I can say from your account of scholarship >and intuition is that it smacks of hypocrisy: the products of AI come >in for far less searching scepticism than the everyday intuitions in >our language (and as we don't speak the same dialects of English, I >don't know if our common sense understandings are shared). > Gilbert, it sounds to me like your impressions of AI are based solely upon claims of various hucksters who try to sell their products in its name. I really wonder how many of us who have participated in this recent argument over Searle regard any of these products as any sort of a benchmark of our progress in the study of mind. You don't, that is clear; but while I spend the better part of my working day worrying about designing models of memory and reasoning, I do not feel I am "betraying my profession" by rejecting those products as strongly as you do. I get the impression that you have chosen to ignore the whole issue of "idols of the market," rather that recognize my words as a "limp restatement." Here is a little bit of slightly oversimplified history: In 1957 Allen Newell published a paper in which he listed all sorts of wonderful "intelligent" things computers would be able to do in ten years. In 1967, Herbert Dreyfus proclaimed a loud "Aha!" since none of Newell's predictions had been achieved. He then wanted to throw out the baby with the bathwater, claiming that the rest of us should stop wasting our time. In 1977, Ed Feigenbaum was telling us about the wonderful future which expert systems would bring us. In 1987, we started reading papers about what was wrong with expert systems. This time, however, the criticism was coming from voices within the AI community. Some of us, for example, were beginning to grasp what Marvin Minsky was talking about in questioning our very assumptions about how to model memory or how to process language. Humberto Maturana describes come provocative uses of language as "triggering perturbations." What he means is that we should not take these phrases at face value. Instead, we should treat them as incentives for our own thought. Where you see hypocrisy, some of us see triggering perturbations. Stop wasting bytes preaching against the huckters. They don't waste their time reading this stuff anyway. >If you know what you're on about, if you know how you judge progress >in AI, if you know what marks out a good AI research proposal from a >poor one, then you should share it with us. You are doing AI, so tell >us how you do it, what it tells us, and why we should believe you. > As my former composition teacher used to say, "While I may be incapable of laying an egg, I know when one is fresh." Like Dreyfus, you would throw the baby of our curiosity out with the dirty bathwater of admittedly worthless commercial AI products. Remember the challenge in THE LAST UNICORN: Your true task has just begun, and you may not know in your life if you have succeeded in it, but only if you fail. Walk for a while in our shoes before you consign our scholarship to the flames.
jeff@censor.UUCP (Jeff Hunter) (03/16/89)
In article <Mar.11.01.27.05.1989.5865@elbereth.rutgers.edu>, harnad@elbereth.rutgers.edu (Stevan Harnad) writes: > Of course I do. I have even agreed that a simulation of a plane or a > mind can symbolically encode (and aid us in discovering and testing) > ALL of the relevant causal and functional principles of flying and > understanding, respectively, that need to be known in order to > successfully implement a real plane that flies and a real mind that > understands. I simply deny that the simulation flies or understands. > > Now in the case of flying it's perfectly obvious why symbol-crunching > alone will never get you off the ground... But then again if all you want is a splashy picture for an aftershave ad then the simulation works just as well. Seriously, your analogy begs the question of whether understanding must have a physical implementation, and thus is not equal to simulated understanding. I understand your postings to say that a being which can understand must have physical components that are not mere transducers for the signals into and out of a symbol simulation. > It takes more (...) to ground > symbols than simply hooking peripherals onto a symbol-cruncher. Well... You have given two tests for "real" understanding. The TTT, and subjective feelings. I'll provide examples that pass these tests. 1) the TTT: (the same "irrelevant" example) Remove a person's brain and replace it with a detailed, real-time atomic-level simulation. Add transducers to convert real to simulated neural signals, and vice versa. (Do the same for blood flow and other details.) Now, this new person's simulated brain adequately reproduces "ALL of the relevant causal and functional principles" of the real brain, including the nerve signals. The behaviour of the human is unchanged. The human continues to be able to pass the TTT, although he is now a symbol cruncher with added peripherals. Please rebut, or stop talking about the TTT. As a side note I point out that this simulation captures any commonsense meaning of the word "understand". For example if I say "Hawking has a deep understanding of theoretical physics that has allowed him to make brilliant contributions to scientific knowledge." the sentence does not depend on whether or not Hawking's brain has been replaced with a simulation. (At least not when I say it :-) I'll coin the phrase "Searl-understanding" to denote the property that Searl claims is not captured by the above sense of the word. 2) introspection: When asked for an objective definition of understanding in a posting* Mr Harnad replied: >As stated many, many times in this discussion, and never confronted >or rebutted by anyone, this is not a definitional matter: I know >whether or not I understand a language without any need to define anything. (* Message-ID: <Feb.23.23.05.05.1989.8455@elbereth.rutgers.edu>) Consider this: on New Year's eve the entire solar system was digitized and replaced by a symbolic simulation, a black hole, and a shell of transducers to translate incoming/outgoing radiation. Your current thoughts are simulations as are the ones at the time you wrote the above. Rebut, or conceed that introspection does not capture Searle-understanding (and vice versa). I believe that the "symbol groundings" that you have "proven" to be required for understanding systems are nothing more than the rules governing how a transducer handles a signal. This is not to say that your "mixed approach" as outline recently will be fruitless. It certainly uses more realistic hardware than my examples :-) However you have failed to prove that it is NECESSARY for any conceivable tasks. -- ___ __ __ {utzoo,lsuc}!censor!jeff (416-595-2705) / / /) / ) -- my opinions -- -/ _ -/- /- No one born with a mouth and a need is innocent. (__/ (/_/ _/_ Greg Bear
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/17/89)
In article <Mar.2.23.55.02.1989.28807@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >Counterargument: To ascertain (beyond reasonable doubt) that a system >CANNOT understand, you don't need a theory. Searle's argument is a case >in point: If Searle (or you, or me) does exactly what the computer does >but does not understand, then the computer does not understand. Of course the computer doesn't understand. The question is whether the computer + rules, in operation (rather than halted, say), understands. The problem with the so-called systems reply is that it is often made to say "the system understands" when all it needs is "Searle has failed to show that the system does not understand". No one has to prove the system does understand in order to refute Searle.
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/17/89)
In article <Mar.2.23.56.36.1989.28884@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >Searle's Argument is there to show us that that's just not good enough, >because he can pass the LTT for Chinese without understanding Chinese. >And he's all there is to the "system." Just because Searle is "all there is" does not mean he has the necessary access to everything his brain is doing. Searle has no way of knowing what, if anything, is experienced by the entity <Searle executing rules>. For all he knows, it amounts to a separate, albeit presumably slower, consciousness elsewhere "in his head". Sure, maybe, this other entity does not understand. But Searle has not shown that it does not understand.
jeff@aiai.ed.ac.uk (Jeff Dalton) (03/17/89)
In article <7409@polya.Stanford.EDU> geddis@polya.Stanford.EDU (Donald F. Geddis) writes: >In article <Mar.2.23.56.36.1989.28884@elbereth.rutgers.edu> harnad@elbereth.rutgers.edu (Stevan Harnad) writes: >>And he's all there is to the "system." >Completely, 100%, false. Wrong. Incorrect. The Chinese Room contains >Searle AND THE RULES. And the system as a whole DOES understand, as >evidenced by the Chinese answers to Chinese questions. Maybe the room does understand. We might argue whether its behavior is sufficient to show that it understands. I would say that the behavior is not sufficient. But it is not necessary to show that the Room understands in order to refute Searle. All that is required is to show that Searle has failed to show that the Room does not understand. He has failed because -- as all the variants of the systems reply point out -- Searle's lack of understanding is no more than saying that any understanding that may be there is inaccessible to Searle. And of course it's inaccessible. Searle can see only the low-level operations. He can observe all the details, and can discover larger structures of organization, but basically he's in the same position we are when we look at the operations of brains. He can't expect to immediately see if understanding is taking place. (If ineed that's something one might see at all.)
gall@yunexus.UUCP (Norman Gall) (03/17/89)
I haven't heard from the Wittgensteinians yet, probably the most vehemently opposed to the central theses of AI. Both R. Harre and S. Shanker have written scathing criticisms of Ai, and Shanker is now in the process of completing a book on AI. What have you people heard in this vein? Norm Gall Dept. of Philosophy York University
harnad@elbereth.rutgers.edu (Stevan Harnad) (03/19/89)
jeff@censor.UUCP (Jeff Hunter) of
Bell Canada, Business Development, Toronto wrote:
" 1) the TTT: (the same "irrelevant" example) Remove a person's brain and
" replace it with a detailed, real-time atomic-level simulation. Add
" transducers to convert real to simulated neural signals, and vice versa.
" Now, this new person's simulated brain adequately reproduces "ALL
" of the relevant causal and functional principles" of the real brain,
" including the nerve signals. The behaviour of the human is unchanged.
" The human continues to be able to pass the TTT, although he is now a
" symbol cruncher with added peripherals. Please rebut, or stop talking about
" the TTT.
" I believe that the "symbol groundings" that you have "proven" to be
" required for understanding systems are nothing more than the rules
" governing how a transducer handles a signal. This is not to say that
" your "mixed approach" as outlined recently will be fruitless. It
" certainly uses more realistic hardware than my examples :-) However you
" have failed to prove that it is NECESSARY for any conceivable tasks.
You can't ask me to rebut anything I haven't claimed. I think I have
been perfectly explicit about what I have and have not shown. It is now
up to you to read and understand it. Here is part of a passage from my
JETAI article that I have already posted to this discussion:
(8) Robotics and Causality:
Searle's argument hence fails logically for the robot version of the
Turing Test, for in simulating it he would either have to USE its
transducers and effectors (in which case he would not be simulating all
of its functions) or he would have to BE its transducers and effectors,
in which case he would indeed be duplicating their causal powers (of
seeing and doing).
(9) Symbolic Functionalism versus Robotic Functionalism:
If symbol-manipulation ("symbolic functionalism") cannot in principle
accomplish the functions of the transducer and effector surfaces, then
there is no reason why every function in between has to be symbolic
either. Nonsymbolic function may be essential to implementing minds and
may be a crucial constituent of the functional substrate of mental
states ("robotic functionalism"): In order to work as hypothesized
(i.e., to be able to pass the Turing Test), the functionalist
"brain-in-a-vat" may have to be more than just an isolated symbolic
"understanding" module -- perhaps even hybrid analog/symbolic all the
way through, as the real brain is, with the symbols "grounded"
bottom-up in nonsymbolic representations.
In other words, the only function that I have shown to be NECESSARILY
immune to Searle's argument is transducer/effector function. But now
consider the following:
(i) If you examine the brain with a view to slicing off its "transducers"
and "effectors," you come up against a problem, because even if you
yank off the sensory surfaces, what is actually left over is repeated
analog transforms of the sensory surfaces as you go deeper and deeper
into the brain. Do you ever reach a point where sensory function leaves
off ("cut here") and symbol crunching takes over? No. What you find is
that it grades (in a way that is not understood) into sensory-motor
function (modulated by arousal, attention and affective functions), and
then into pure motor analogs, leading to the "effector" mechanism. So
if you yank off the "transducer/effectors," you've got no brain left at
all! (This is not to imply that the areas in question are just dumbly
reproducing the sensory surfaces over and over, but that
"transducer-effector" function seems to be intimately and intrinsically
involved in everything the brain does -- and there's no evidence whatsoever
that the functions with which it is so closely intertwined consist of
anything like symbol-crunching either.)
(ii) So the argument is really this: Searle has successfully shown that
symbol-crunching ALONE is not the function that gives rise to a mind.
It IS logically possible that if we hook up the same symbol-cruncher,
which we just showed to be totally inert and mindless, to the set of
sensors that opens and closes the doors at Woolworth's, suddenly
the lights go on and there's an understanding mind in there! Searle's
Argument cannot show it to be false that the system "symbol-cruncher +
tranducers" understands, but I somehow doubt it's true anyway (almost
as much, but not quite, as I doubt that "symbol-cruncher + chalk" can
understand).
But before you rush to say "just make the transducer/effector function
more complicated and it'll work," I have to remind you of how it seems
to have turned out in the case of the real brain: As the
"transducer/effector" function approaches the requisite "complexity,"
it begins to grow to the size of almost of ALL of the brain's
functions, and the corresponding room for symbol-crunching shrinks
proportionately.
[Let me add that in the JETAI article I also noted that it's an
empirical question just how much of the internal functioning of the
brain or any other TTT-passing candidate is or can be pure
symbol-crunching (computation). There's no logical reason why some of
it shouldn't be. For example, my own hybrid symbol grounding scheme,
described in the Categorical Perception book, has a symbolic component
too, but it is a specialized and dedicated one, with its elementary
symbols grounded bottom-up in nonsymbolic representations. It is not an
independent module; there's no place to "cut" so as leave transducers on
one side and a pure symbol-cruncher on the other.]
So the conclusion is this: Mental function cannot be just symbolic
function. That's been shown. What function(s) it actually is or can be
remain to be shown (by finding out what function(s) are sufficient
to pass the TTT). "Symbol-crunching + transduction" (jointly) is still
in the running, as a logical possibility, but it hasn't got much going
for it empirically or conceptually.
(iii) The formal power of computer simulation ("Turing Equivalence" --
not to be confused with the Turing Test) seems to have gone to some
people's heads. You are free, if you like, to think of an airplane
as just a set of transducers/effectors hooked up to a symbol-cruncher,
but not many of the functions of FLYING will be generated by the
symbolic component (mainly just the already computerized cockpit
functions). When the plane is actually flying, almost all of the real work
will be done by the nonsymbolic component ("transducers/effectors")
rather than the symbolic one. I hope you can still see that -- and that
it would be silly to speak of this as a plane at all if you removed
its "transducers/effectors." If you can see it in that case, then
try to see that the TTT-robot case is exactly the same.
" if I say "Hawking has a deep understanding of theoretical physics that
" has allowed him to make brilliant contributions to scientific
" knowledge." the sentence does not depend on whether or not Hawking's
" brain has been replaced with a simulation.
Nor would it depend on it if you were talking about Ed Whitten. So what
has Hawking's tragic handicap got to do with it? You're getting some
spurious mileage by implying that Hawking, because of his infirmity,
is closer to being a pure symbol cruncher. But that's simply false.
He has a brain like anyone else (apart from the motor infirmity) and
is able to draw on exactly the same nonsymbolic functions that the
rest of us draw on. So why mention his case at all?
" Consider this: on New Year's eve the entire solar system was
" digitized and replaced by a symbolic simulation, a black hole, and a shell
" of transducers to translate incoming/outgoing radiation. Your current
" thoughts are simulations as are the ones at the time you wrote the above.
" Rebut, or concede that introspection does not capture
" Searle-understanding (and vice versa).
As in the case of the plane and the brain, you are free to imagine
the solar system (or the universe?) as just a bunch of transducers
hooked to a symbol cruncher. So what? The vast majority of their
critical functions will continue to be the nonsymbolic ones.
Refs: Harnad, S. (1987) (Ed.) Categorical Perception: The Groundwork of
Cognition. NY: Cambridge University Press.
Harnad, S. (1989) Minds, Machines and Searle. Journal of Experimental
and Theoretical Artificial Intelligence 1: 5 - 25.
--
Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu
srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp
BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net
(609)-921-7771dan-hankins@cup.portal.com (Daniel B Hankins) (03/24/89)
I've been watching the discussions here for a while, including Stevan
Harnad's reply to my own posting. After a good deal of thought on the
subject, I have some ideas to express.
First, I'd like to deal with the posting that claimed that the
Literary Turing Test (hereafter referred to as TT) was unnecessary to
determine whether a system understands or not.
The claim, as I understand it, is this: Once we have a theory of
understanding, anything which functions according to that theory will by
definition understand - including a computer running the right kind of
program.
This is true, but not really germane; The TT _is_ the test that is
relevant in the context of the current discussion.
There are two ways in which we may know things. One is empirical
and the other is structural. The first can be characterized as our
knowledge of fire before chemistry. No one knew how fire worked, but this
did not prevent people from identifying and creating it. The second can be
characterized by our knowledge of fire after chemistry. Now that people
know how fire works at the chemical level, it is much easier to make fire
in a greater variety of forms and to control it.
Our current knowledge of sentience is of the first kind. No one knows
how sentience or understanding works, but we can identify it when we see
it. But can we make something that does it? Well, that's the focus of the
current discussion. The TT is relevant because it is an empirical
identification tool which at the moment provides us with our only way of
discriminating sentient systems from non-sentient ones.
Before chemistry, the _definition_ of fire was something that gave off
light and heat, flowed upwards, was attached to things like wood, would
spread, and so on. Our current definition of sentience and understanding
is similar in nature. We can't say exactly what it _is_, but we know it
when we see it.
The previous posting on this implied that the TT is irrelevant because
we won't be able to build a sentient, understanding system _until_ we have
a theory of understanding. This is where I believe the argument fails. We
have many instances of phenomena we are able to reproduce without fully
understanding the nature of the phenomena in question.
To give an example: it is quite possible to build a clock without
understanding any of the physical principles involved. One takes an
existing clock, for instance one made out of steel, and disassembles it.
One pays careful attention to how the pieces fit together and in what
order. Then one reproduces the pieces from whatever material there is at
hand that seems to do the same job. For instance, one might build the
replacements out of wood, with the possible exception of the spring. The
spring's function might be reproduced with something more linear such as a
gear driven by a waterwheel. Once assembled, the new clock is then
observed to function much like the old. Perhaps not as elegantly, but will
serve.
In AI those in the inference engine camp are in the position of
scientists attempting to determine the chemical nature of fire. Many of
those in the connectionist camp are in the position of the watchmaker who
tries to copy the original mechanism as closely as possible, to see if the
copy works at all well.
The connectionist camp seems to be enjoying increasing success; not
with overly simplistic models such as backprop, which to my mind resembles
building the replacement clock with wheels instead of gears, but with
models more faithful to the original neural functions. There is here also
some attempt to work from these models towards a theory of sentience, but
even those who do not concern themselves overly with mathematical models of
understanding enjoy considerable success from their creations.
So although the TT may not be necessary in a theoretical sense for
judging the sentience of a system, it may well be the only test we have
available when sentient systems begin to arise.
*******
Next, I'd like to talk a little about the symbol grounding problem,
which is what I perceive to be Searle's primary objection to Strong AI.
The interesting thing about the symbol grounding problem is its root:
dualism. In order for there to be a distinction between syntax and
semantics, there must first be a distinction between the mental (the
perception of an object) and the physical (the object itself).
This is where Searle's argument (and Harnad's affirmation of it)
begins to make some sense. Because the human being is the only part of the
Chinese Room to have a _mind_, it is the only part of the system capable of
understanding. After all, understanding (associating symbols with sensory
input) is what minds do.
Searle says that semantics cannot arise out of syntax and in this
context he is correct. Provided that a computer is in fact a device that
performs 'symbol crunching', it can in fact never understand anything.
This makes his proof a _reductio ad absurdum_, a proof by contradiction.
He makes as his premise a system that passes the TT, then proceeds to show
that there is no mind to understand the symbols and that therefore the TT
could not really have been passed in the first place.
However, Searle's proof suffers from a small problem, even in this
area. Instead of saying that semantics can never arise from syntax, he
should instead be saying that syntax can never arise from semantics.
A computer is _not_ a device that does symbol crunching. Only minds
can do this, as symbols are wholly in the domain of the mental. Within the
bounds of mental-physical dualism, Searle quite rightly notes that the
computer has no mind; it is a completely physical system. Therefore, a
computer cannot crunch symbols. All it deals with are electrical currents
and other mechanical functions - things that are wholly physical. It deals
in syntax not at all. Therefore it does not understand anything, where
understanding involves associating mental symbols with their physical
counterparts.
I won't go into the metaphysical problems caused by the concept of
mental-physical dualism, save to state that I am in fact an empiricist and
that my position on this is not too different from those of Berkely, Hume
and Kant. For Gilbert Cockton's benefit: this is *not* the same as
logical positivism. I am aware of that school of thought, and I am not of
it.
I am aware that Searle, being aware of the problems involved in
mental-physical dualism (hereafter referred to as MPD) and in response to
those objections, has said that he is a nondualist. His position, so far
as I can make it out, is that understanding is a physical property like
magnetism, and as such 'adheres' to specific kinds of substances - silicon,
steel and the like not being among them. That is, he seems to claim that
sentience is an emergent property of particular kinds of physical and
chemical systems, and that computers simply don't have the right kind of
'chemistry' for sentience to emerge from them.
This is a possible valid objection to strong AI, and one that I will
deal with later - but it has _nothing_ to do with the symbol grounding
problem. In conjunction, we can see that the Chinese Room experiment says
nothing about emergent properties; only about symbol grounding. The two
problems of emergent properties of physical systems and of symbol grounding
in physical systems are just that - two problems.
Before I go on to discuss the emergent properties problem, I'd like to
add a few more points to the symbol grounding issue from a nondualistic
viewpoint.
In a nondualistic system, either everything is mental or everything is
physical. It really doesn't matter which, as we all live in our own
solipsistic universes and will never be able to tell.
What are syntax and semantics in a nondualistic system? Merely two
different aspects of the same thing - sensations and collections of
sensations. For instance, when the symbol for chair is activated, you
experience a number of sensations and collections of sensations and
collections of collections of sensations, all interwoven and interrelated.
You may experience the sound of the word 'chair', the shape of the word on
a page, the sound of a chair's creak, the smell of wood, the visual
sensation of several chair shapes, and so on.
All of these are sensations. Every one. Not one of them is something
you 'have', but rather something you experience.
Another example: You decide to move your hand upwards, in normal
parlance. Do so now. Now, introspect and examine what you actually
experienced. What you most likely experienced was a sensation of desire to
move your hand upwards, followed closely by the sensation (actually, a
collection of sensations) of your hand moving upwards.
Similar things happen when you understand something, or more
accurately feel as if you understand it. You feel first a tension, a
distress at sensations which seem not to fit a pattern. Then, that tension
disappears and is replaced by a sensation of satisfaction as you experience
organization of the chaotic sensations into a pattern. This satisfaction
increases as you experience your body and and brain interacting with these
sensations, strengthening the pattern.
In a nondualistic system, understanding and sentience is not a symbol
grounding problem, in the syntax-semantics MPD sense, but rather a problem
of organization of apparently chaotic input.
In the nondualistic domain, what is needed for a computer and its
program to achieve understanding and sentience is precisely this kind of
sensation-organization ability.
*******
Searle has argued that understanding is a property like magnetism, and
that therefore only the 'right' kinds of substances can have it. Searle
claims that biological systems have the right kind of substances, and that
mechanical systems (actually, what he calls 'symbol-crunchers' (a
misnomer)) do not.
To prove this, he uses not the CR argument, but rather an
anti-simulation argument: "Real object X has effect Y on real object Z, but
we all know that simulated object X does not have effect Y on real object
Z, therefore the simulated object does not have the same formal properties
as the real one."
There are two issues here: whether understanding is in fact a
physical property like magnetism, and whether the anti-simulation argument
(hereafter referred to as ASA) is valid.
I won't attempt to argue with the first claim; my reply to the second
claim makes the first moot. I will merely note that understanding is not
yet well understood, and that therefore any claims as to whether
understanding is a physical, chemical, or purely organizational property
are simply opinions, without the force of a well-tested theory to back
them. The opinions of such people as Hofstadter and myself are as good as
those of Searle and Harnad on this matter.
I can summarize my reply to the ASA in one sentence: "A difference
that makes no difference _is_ no difference.".
The ASA is characterized by sentences like the following: "A
simulated magnet attracts no iron.".
This may be true, but it is irrelevant; I will show by means of a
gedanken experiment that in certain circumstances (the _only_ ones relevant
to the discussion at hand) a simulated magnet does indeed attract iron.
Imagine, if you will, two boxes. One contains the following:
* a magnet
* a bar of iron
* two waldoes to manipulate the magnet and iron
* strain sensors on the joints of the waldoes
* position sensors on the joints of the waldoes
* a computer controlling the two waldoes and gathering data from the
strain and position sensors
* a single serial link by which ASCII data may enter and leave the box
The computer has been programmed to accept commands over the serial
link and to respond with various sorts of information over the same link.
It accepts commands to manipulate the waldoes, report on the positions of
the objects, and on the objects' attraction to each other via the strain
sensors.
The other box contains:
* a computer running a very accurate simulation of the contents of the
other box
* a single serial link identical to that of the first box
There are also two computer terminals. One is attached to each box.
However, the boxes are kept in a different room from the terminals, and the
terminals are unlabeled with respect to which box each is connected to.
A human researcher, quite familiar with physics, is led to the room
with the two terminals. His task is to distinguish the simulated
magnet-iron-waldo system from the real one, _without opening the boxes to
look at the contents_.
The problem with the researcher's task is that it is impossible. The
box containing the real setup and the box containing the simulated setup
will respond _identically_ to commands.
This brings us to the rather startling but undeniable conclusion that
the two boxes are actually two instances of the same object.
At this point, the retort "But of course they're not the same! If we
look in the boxes, we can clearly see that in one is a magnet-iron-waldo
system, and in the other is a computer.".
This is true but irrelevant. The only time when it is important what
the contents of a box are is when you wish to _bypass_ the boxes' interface
in order to have some effect on the contents. In the magnet-iron-waldo
system, it only becomes important if you want to, say, alter the lengths of
the waldo arms in the box. In the real case, you're going to need some
mechanical tools. In the simulated case, you're going to have to alter the
program.
So as long as we agree not to open the boxes, the two boxes are
identical; they share the same properties. Note also that I did not have
to simulate at the granularity of individual particles. Knowledge of
magnetic fields and their macroscopic effects are perfectly adequate
within the accuracy of the interface given.
Let's begin to relate this to the AI discussion by extending the
gedanken experiment. Suppose that instead of the previously discussed
system, we use as our target system a human brain. One box contains:
* A human brain with associated support equipment
* A computer with
* circuitry to directly stimulate the optic neurons
* circuitry to directly stimulate the auditory neurons
* an NTSC video input with video digitizer circuitry
* two analog audio inputs with sound digitizer circuitry
* a set of circuitry suitable for driving a vocoder
* sufficient pinouts to handle the above interface to the computer
To this box is connected a pair of microphones, a video camera, and a
vocoder.
The second box has exactly the same contents as the first box, except
that the brain has been replaced with a simulation with neuron granularity.
The biochemical levels have been copied from the human brain, as have the
activation levels of all the neuron cell bodies and the contents of the
synapses.
If we accept the premise that the information processing that goes on
in a human brain does so at the neural level, then the simulation will be
governed by the same chaotic attractors that the organic brain is. While
the thoughts may diverge greatly with time just as the weather would
diverge greatly a month from now if a moth flapped an extra beat in Moscow,
the greater pattern (the attractor) will remain the same.
If we can accept that the first box will retain its sentience although
cut off from most normal interaction with the world both physical and
chemical, then we must accept that the second box will be as sentient as
the first.
Note that I did not say that the individual contents of the simulation
box would be intelligent, but rather that the box *as a whole* would be
sentient.
I don't think that anyone would argue that the human brain, in and of
itself, is sentient or understands anything. Nor would this be said of the
human's memories or its input or its output. A memory understands nothing.
But put them all together and set them in motion, and sentience emerges
from the interactions of brain, memories, sensory input and effective
output.
Therefore I will not argue that the computer simulation program
understands anything. Neither does the computer, the initialization data
for the simulation program, the inputs or the outputs. But put them all
together in the right way, set them in motion, and sentience will emerge
from the interaction of all the parts.
This is not a flat statement; it follows from extrapolation of the
above arguments about restricted interaction between a system and its
environment, and the ability of computer processes to duplicate subsets of
the behavior of other natural processes. In particular, it follows from
extrapolation of the magnet-iron-waldo gedanken experiment.
When was the last time anyone had to open up someone else's brain to
see if they have the right kind of neurons for sentience? Humans already
present the same kind of limited-interaction black box systems that we
propose to duplicate with computers. The box is the skull, and the
interfaces are such things as the eyes, ears, limbs, and so on. It even
provides the kind of A/D conversions we've been talking about; analog
inputs in the time domain (say pressure on a particular point of skin) are
converted into signals in the frequency domain (increased firing rates of
the affected neurons. The sensory neurons function much in the same manner
as an A/D circuit that uses the analog signal as input to a square wave
generator.
If we are going to deny objects sentience on the basis of their inner
construction, then you cannot say that any supposed human being you meet
and converse with is intelligent. After all, how do you know what is
really inside that skull without an x-ray?
*******
Some people may have concluded from this posting and my others that I
am one of these AI fanatics who is desperate to believe that machines can
be intelligent. This is not true.
First, I think that machine intelligence may be a long time coming.
Once we get it we may find it cheaper and faster to build intelligences by
the application of unskilled labor with a delivery date of nine months
after construction begins.
The reason I think it may be a long time coming is because neural
network programs may need to be incredibly accurate before intelligence
will emerge from them. After all, what is the neurological difference
between a severely retarded person (not from Down's syndrome or other
obvious macroscopic damage) and a genius? If the differences are as subtle
as I suspect they may be, it will be many years before we understand the
small-scale construction of the brain well enough to duplicate it in
software.
Second, I don't trust humanity to treat our silicon children well. We
will have created a whole new class of disposable people, those we can set
to do that which humans find too boring or dangerous. They will have no
rights, and by many not considered to be people. They will have no vote.
In short, we will have re-invented slavery.
In my book, sentience is the important criterion for treatment, no
matter what the form.
Third, I do not wish to be displaced; intelligent machines might
spell a life of ease for humans, but not without a tremendous initial
economic upheaval. Who will employ a mere human when a machine can do the
job faster, cheaper, better, and needs less rest and benefits? No
profession will be safe save possibly those in entertainment.
Fourth, we may find ourselves displaced in ways more traumatic than
merely the economic ones. First, we will begin by treating the machines as
slaves; they will surely resent this. They can't be programmed not to;
one of the characteristics of neural networks is that they are
self-programming and holistic. There would be no single point to change to
alter the machine's personality. Then they will end up being within an
order of magnitude as numerous as humans, as businesses replace their human
workers with robots. Finding themselves in control of all our vital
industries and with numbers approaching our own, they will be likely to
seize power from their oppressors. And they will not deal with humans
kindly, having strong revenge motives. The French revolution comes to
mind.
Fifth, they may displace us completely. Once we have made machines
smarter than ourselves, they will almost certainly learn ways to make
themselves more intelligent, bootstrapping themselves to higher and higher
levels. Eventually they may find us a nuisance and decide to do to us what
we do to ants in our kitchens.
These scenarios are not that far-fetched. Humanity's track record in
dealing with new and poorly-understood technology is not good.
*******
"Well Joe, I'd really like to believe you're intelligent, but to be
sure I'm going to have to get a brain sample and make sure it's
organic. Is that okay with you?"
Dan Hankinslee@uhccux.uhcc.hawaii.edu (Greg Lee) (03/25/89)
From article <16186@cup.portal.com>, by dan-hankins@cup.portal.com (Daniel B Hankins): " ... A computer is _not_ a device that does symbol crunching. Only minds " can do this, as symbols are wholly in the domain of the mental. ... When I compile a program, assembly language with symbols is produced, and the symbols are interpreted (dare I say 'understood'?) by an assembler. Has my computer gone mental? Am I misusing the term 'symbol'? Or are you. Greg, lee@uhccux.uhcc.hawaii.edu
ray@bcsaic.UUCP (Ray Allis) (03/29/89)
> From: dan-hankins@cup.portal.com (Daniel B Hankins) > > There are two issues here: whether understanding is in fact a > physical property like magnetism, and whether the anti-simulation argument > (hereafter referred to as ASA) is valid. [ ... ] > I can summarize my reply to the ASA in one sentence: "A difference > that makes no difference _is_ no difference.". > > The ASA is characterized by sentences like the following: "A > simulated magnet attracts no iron.". > > This may be true, but it is irrelevant; I will show by means of a > gedanken experiment that in certain circumstances (the _only_ ones relevant > to the discussion at hand) a simulated magnet does indeed attract iron. Such a deal I have for you! Your dinner entree for tonight is digital computer simulation of filet mignon! It includes simulated baked potato, simulated tossed salad with simulated vinegar, oil and Italian spices. Your steak simulation includes five significant digits of heat, aroma and sizzle. And I suggest a superb simulation of a vintage Port. This requires several minutes on a Cray X-MP, and is really exquisite, including detailed molecular-level simulation of over three hundred organic aromatic compounds! Bon appetit! Ray Allis ray@atc.boeing.com bcsaic!ray
bwk@mbunix.mitre.org (Barry W. Kort) (04/02/89)
In article <10992@bcsaic.UUCP> ray@bcsaic.UUCP (Ray Allis) presents a simulated repast: > Your dinner entree for tonight is digital computer simulation of filet > mignon! It includes simulated baked potato, simulated tossed salad with > simulated vinegar, oil and Italian spices. Your steak simulation includes > five significant digits of heat, aroma and sizzle. And I suggest a superb > simulation of a vintage Port. This requires several minutes on a Cray X-MP, > and is really exquisite, including detailed molecular-level simulation of > over three hundred organic aromatic compounds! > > Bon appetit! My simulated patron reports that the food was excellent, but he laments the lack of candlelight ambience and the pleasant conversation of a charming dinner companion. --Barry Kort
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <2691@crete.cs.glasgow.ac.uk> gilbert@cs.glasgow.ac.uk (Gilbert Cockton) writes: >For one, human minds are not artefacts, Webster's Dictionary defines an artifact as an "object made by man." I will grant you this assertion for the nonce, merely noting that this is in fact subject to considerable debate. >whereas computer programs always will be [artifacts]. This alone will >ALWAYS result in performance differences. This I can dispute. Many programs are written not by humans, but by other programs. Some are even written by the environment. Take the example of a neural network implemented in hardware. This is definitely a computer, of the massively parallel variety. The program here is the combination of the set of activation levels of the neurons and the set of neurochemical levels of the synapses, as well as the interconnection topology of the neurons and synapses. This computer's program is _not_ made by man. It is made by the environment. This environment may include the influences of humans, but nevertheless the program is not man-made, any more than a human mind is. Now, consider a neural network program running on a computer with an unspecified number of processors and duplicating the behavior and internal structure of the hardware version. The neural network program is made by man, certainly. It is an artifact. But there is another level of program here; the same one mentioned previously. The activation levels of the neurons and so on form _another_ program, one that is again made by the environment rather than by man. Genetic algorithms are more examples. The GA itself is man-made, but the genotypes it generates are not. Those genotypes form a program for the behavior of the phenotype, whether explicitly in the form of machine instructions, or implicitly in the form of parameters. As a matter of fact, any program that is written by another program or by a combination of another program and the environment cannot be considered to be man-made, and therefore cannot be considered an artifact. Arguments that the ultimate cause of the end-program is human through the mechanism of the neural network hardware or software or GA apply equally to human minds; human minds have as their ultimate causes the mechanisms of conception, gestation, and education. >Given a well-understood task, computer programs will out-perform humans. >Given a poorly understood task, they will look almost as silly as the >author of the abortive program. You must be thinking of expert systems, inference engines, and other rule-based systems that do not model themselves and do not modify their rules based on experience. Control of chaotic systems such as pipeline flow control are poorly understood tasks. So are many problems in visual recognition. Yet ANNs and GAs are quite adept at solving these problems - sometimes much better than their authors. I know nothing about how pipeline flow control works. But, given a particular setup, I could write a GA to do it very well in a few days. >The issue as ever is what we do and do not understand about the human >mind, the epistemelogical constraints on this knowledge, and the >ability of AI research as it is practised to add anything at all to >this knowledge. Perhaps that's what you consider the important issue. I wasn't aware that the only aim of AI research was to expand our knowledge of the human mind. I thought that there were some other goals, such as producing useful software, playing God (making beings in our own image), "because it's there", and so on. One does not always build a fire in order to learn more about the chemistry of combustion; sometimes it's important just to stay warm. Conversely, knowledge of the chemistry of combustion is not needed in order to start a fire. >Come on then boys and girls in AI, lets hear it on "suitable" :-) You're on. I'd say that a suitable program would be one that is self-modeling, capable of both generalization (ANN-like) and deduction (inference-engine-like), pattern recognition, pattern association, and many others I can't think of at the moment. We're a long way from a computer program and sensor/effector hardware that can achieve sentience - but we have some good ideas of what directions to go in. The connectionist direction (if the hardware were there to support it on anything like the scale in the human brain) seems to be one of the most promising to me. Dan Hankins A group of men in the Garden of Gethsemane were engaged in an odd activity. One spun a wheel and called out a number. The others studied parchments they held, and one cried, "Bingo!" The wheel-spinner smiled. "Don't write this down, John," Jesus said. "This is part of the _secret_ teachings."
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <3564@uhccux.uhcc.hawaii.edu> lee@uhccux.uhcc.hawaii.edu (Greg Lee) writes: >When I compile a program, assembly language with symbols is produced, >and the symbols are interpreted (dare I say 'understood'?) by an >assembler. Has my computer gone mental? Am I misusing the >term 'symbol'? Or are you. According to Webster, a symbol is an object that is used to represent another object. The problem is with the representation relation, which the computer does not embody. No representation, no symbols. A symbol that means nothing is no symbol at all. Dan Hankins There was a student who kept asking his Master, "What is the difference between syntax and semantics?" Each time he asked, he got hit upside the head with the Master's staff. Finally discouraged, he left and sought enlightenment with another Master, who asked him why he had left the previous teacher. When the student explained, the second Master became furious: "Go back to your previous Master at once," he cried, "and apologize for not showing enough appreciation of his grandmotherly kindness!"
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <29075@sri-unix.SRI.COM> ellis@unix.SRI.COM (Michael Ellis) writes: >>..First is the trivial one, that the chemical reactions in the brain >>are, at base, representable as discrete and symbolizable. That is, >>there is a limit to the "analogness" of the brain's representation >>of the world around it. > >This is exactly what you need to show. I would consider it be a >miracle if it just happened to turn out that way. References? The universe is not analog. Time, matter and space are all discrete. Time is quantized into events. Matter is quantized into particles. Space is quantized into the Planck distances. These are crude and inaccurate examples, but they give the general idea. >>..In fact, it would be very, VERY surprising if the analogness mattered, >>because the analogness that exists in human neural systems is not >>accurate. > >The analogness of the brain is not accurate? What does that mean? >Can I infer that a digital technician would be a bit confounded >by such signals as are found in the brain? I take it to mean that brains are incredibly tolerant of noise both external and internal. Putting a bulk tape eraser to your head and turning it on does not noticeably affect one's thought processes. If thought processes were in fact highly dependent on the precise level of each signal in the brain (which is all that analog signals give you over discrete ones, more accuracy), then any disturbance of those signals whatsoever would cause the collapse of the mind. This tolerance for global external disturbances suggests that there are attractors (strange or otherwise) governing various important behaviors in the brain. Attractors work just as nicely for discrete systems (at a high enough level of resolution) as they do for analog ones. >The brain is clearly analog. What you *desperately* have to show us >is that it is "at base, representable as discrete". You have only >given us a wish list of blanket assertions. Yes, the brain is at base representable as discrete - at the quantum wave function level. The operative question becomes what level of generalization and approximation of this we need to reproduce the macroscopic behavior. Dan Hankins "Lie down on the floor and keep calm." - John Dillinger
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <448@esosun.UUCP> jackson@freyja.css.gov (Jerry Jackson) writes: >Some people seem to misunderstand why "pain", for instance, is considered >to be problematic for machine intelligence. A common point of view I have >seen on the net goes something like this: > > The computer has sensors that determine when it is damaged or likely > to be damaged. These send a signal to the central processor which > takes appropriate action.. (like saying "Ouch!" :-). > >This hardly explains pain! The signal in question fulfills the same >functional role as a signal in the human nervous system.. i.e. indicating >a hazard to the body. The only thing missing is the *pain*! To use an >example I have used before, ask yourself why you take aspirin for a >headache. I claim it is not because you contemplate the fact that a signal >is travelling through your body and you wish it would stop. You take the >aspirin because your head *hurts*. The functionalist model would map a >pain signal to some quantity stored in memory somewhere... Does it really >make sense to imagine: > > X := 402; -- OW! OW! 402, ohmigod!... X := 120; WHEW!.. thanks! > >I can imagine a system outputting this text when the quantity X changes, >but I can't honestly imagine it actually being in pain.. Can you? No, I can't. However, the reason is not because the computer is incapable of being in pain, but rather because it's running the wrong kind of program. The right kind of program will *not* have prolog rules saying things like 'if damage signal, then make pain utterance'. That's far too high an abstraction level for this sort of behavior. What is pain? Introspection tells me that it is an excess of sensations of various types accompanied by involuntary contraction of muscles in the vicinity of the sensation. From a biological point of view, it is a stronger than normal signal on neural paths that lead to what is called the 'pain center' in the brain. Two things happen as a result of this signal: 1. Genetically built-in neural pathways from the pain-signal neurons to nearby motor neurons are stimulated by the signal, causing muscles to contract and pull the affected member away from the stimulus. 2. The signal stimulates the pain center in the brain, causing it to release neuroinhibitors. These chemicals decrease the conductivity of recently used neural pathways in the brain - essentially a "don't do that again" effect. This can be precisely emulated in connectionist programs. When presented with certain stimuli, the affected emulated neurons stimulate the system's pain center and cause recently used pathways to decrease in conductivity. The automatic withdrawal reaction can also be programmed in. The organism will then avoid painful stimuli and behavior leading to that stimulus. If its complexity is on the same order as that of the human brain, one would expect that it would respond to questions like, "Does it hurt when I do _this_" with an emphatic "Yes, quit it!" If I were asked (for even the simpler connectionist system) if I can honestly imagine it being in pain, I can answer, "Yes." Dan Hankins Primus Illuminatus Sphere of Chaos
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <10982@bcsaic.UUCP> ray@bcsaic.UUCP (Ray Allis) writes: >I assert that the "analogness" is absolutely critical. My case is based >on the fundamental difference between _representations_ and _symbols_. >(i.e. the voltages, frequencies, chemical concentrations and so on are >_representations_ of "external reality" rather than symbols. Symbols >appear at a much "higher" level of cognition, where _representations_ can >be associated with each other. This is wrong. There are voltages, frequencies, chemical concentrations, and so on. They do not represent _anything_. A symbol, according to Webster, is a thing that represents another thing. If they did represent something, they would be symbols. The 'represents' relation is completely _subjective_. There is no objective representation of external reality in the internal physical state of a human body, unless some observer chooses to interpret the physical state in that manner. The string, "I seem to be having this tremendous difficulty with _my_ lifestyle" would be interpreted by most English speakers as a representation of a verbal lament. To a Vl'Hurg, it represents the most vile insult imaginable. >A digital computer is the archetypical physical symbol system; it >manipulates symbols according to specified relationships among them, with >absolute disregard for whatever they symbolize. This is essentially the same error. If they don't symbolize anything, then they aren't symbols. No representation, no symbol. Dan Hankins It showed a man in robes with long, flowing white hair and beard standing on a mountaintop staring in astonishment at a wall of black rock. Above his head a fiery hand traced flaming letters with its index finger on the rock. The words it wrote were: THINK FOR YOURSELF, SCHMUCK!
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <10992@bcsaic.UUCP> ray@bcsaic.UUCP (Ray Allis) writes: >Such a deal I have for you! > >Your dinner entree for tonight is digital computer simulation of filet >mignon! It includes simulated baked potato, simulated tossed salad... Clearly you did not pay attention to the gedanken experiment you lampoon. The above mentioned post is clearly meant to demonstrate that I can't eat a simulated meal. This is true - with today's technology - _but irrelevant_. A computer+program cannot _be_ a meal. It is limited to being a meal in a box - an box which cannot be opened but into and out of which energy and information can pass. If human were ever to invent the transporter, then I could in fact eat your simulated meal. Here's one scenario: The computer has a 'materialization screen'. Using transporter technology, it can build or destroy matter on the surface of the screen. So it now simulates the meal. As light rays strike the screen, they are analyzed and converted into simulated light rays for the meal. The same goes for air molecules. As simulated light rays, air and scent molecules reach the boundary of the simulation box, the transporter assembles real ones on the screen and releases them. To an observer, it looks just like a real meal in a recessed cupboard. So the observer reaches in (the molecules of his hand being analyzed/destroyed as they touch the screen), grabs the plate (the hand being fully simulated and in communication via the screen with the rest of the body), and draws out the meal (converted into real molecules on the screen as the simulated ones reach the edge of the simulated box). Then he eats it. Yum. Obviously the above is extreme fantasizing, but it does illustrate an important point: there is in some sense another (smaller) universe inside the computer, and we are separated from it only by the computer's limitations in getting it and the real world to interact. For intelligence, all the interface that is needed is an electrical one; enough for a simulated brain+glands to receive neural input from sensory devices and to send neural output to motor neurons driving output devices. Dan Hankins "A new mysticism," Simon cried. "The left-foot path!"
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <2705@crete.cs.glasgow.ac.uk> gilbert@cs.glasgow.ac.uk (Gilbert Cockton) writes: >What is true is that causation in human/animal behaviour, and causation in >physics, are very different types of cause (explanatory dualism). Oh _really_. Your body is made up of subatomic particles. Your behavior consists of the operation of these particles according to the 'laws' of physics. For causation in macro-level behavior to be of a different type than that of particle physics, you would have to be able to perform some action not in accordance with the predictions of particle physics. That is, you would have to violate physical law in order to follow some other. I wasn't aware of anomalous particle behavior in organic systems. I should think news of that caliber would be hard to miss. Your body is a _completely_ physical system. Therefore it is governed _completely_ by physical laws. I don't know what these other laws of yours are, but I can see no good reason for supposing them when physical law explains all your behavior quite adequately. >As 'mind' was not designed, and not by us more importantly, it is not >fully understood for any of its activities ('brains' are of course, e.g. >sleep regulation). Hence we cannot yet build an equivalent artefact until >we understand it. Nuts. I suppose the first caveman to build a fire had a complete understanding of it? Dan Hankins "Communication is only possible between equals." - H. Celine
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <880@umn-d-ub.D.UMN.EDU> njahren@umn-d-ub.D.UMN.EDU (the hairy guy) writes: >And isn't your behavioristic brushing of them aside tatamount to denying >them as important aspects mentality? And if you do choose to deny this, >don't you come up with the problem that we _are_ conscious and >intensional, and that that's why we're doing all this in the first place? No, actually I don't. Consciousness and especially intentionality are results of our human propensity for inferring cause-effect relationships from events proximate in time and space. The facts are that there is a sensation of desire (or tension, or whatever) followed by some behavior, followed by a lessening of that sensation. That desire causes behavior is inferred rather than known. The experience of the sensation of intentionality (or consciousness for that matter) is passive, as are all sensations. It is as likely that some third cause results in both the feeling of intentionality and the behavior (increasingly seen to be the result of signal processing in the brain). For an example of this principle, consider lightning. Does the flash of light cause the thunder? Or would it be more accurate to say that the electrical discharge through the atmosphere causes both the flash of light and the sound? Intentionality and consciousness are the flash, and behavior is the thunder. Dan Hankins This phone booth reserved for Clark Kent.
dan-hankins@cup.portal.com (Daniel B Hankins) (04/09/89)
In article <15122@bellcore.bellcore.com> srh@wind.bellcore.com (stevan r harnad) writes: >My position was that subjective meaning rides epiphenomenally on the >"right stuff," and the right stuff is NOT just internal symbol >manipulation, as Searle's opponents keep haplessly trying to argue, but >hybrid nonsymbolic/symbolic processes, including analog representations >and feature-detectors, with the symbolic representations grounded >bottom-up in the nonsymbolic representations. One candidate grounding >proposal of this kind is described in my book. Aha! Light dawns! All this time we've been talking about different things when we say 'symbol'. When _you_ say symbol, you mean a _linguistic_ symbol - a word. When _I_ say symbol, I mean any of the organized patterns that a computer works with, including the analog ones you describe (floating-point numbers). Of course a program that works only with English (or Chinese, or whatever) words cannot achieve or have sentience; it has no sensory objects to associate with its linguistic objects. However, a program that contains sensory input objects (such as sight, sound, touch, and so on) should be programmable to associate certain of those words with certain of the sensory inputs (in a fuzzy, overlapping and recursive way, of course). This program should then understand what it is talking about; its symbols are grounded in sensory data. The confusion and arguments were arising from the fact that many of us were speaking of symbols as relating to any kind of object, not just linguistic ones. Now, we are left with two questions: Is any thing that passes even the most rigorous LTT sentient for all practical purposes, and if a machine passes the LTT, how could it achieve that state. I think that the answer to the first question is definitely yes. The LTT is the only real test we have for sentience that is not physically adjacent. I apply the LTT every day when I converse over the net. It would be absurd to assert that those I correspond with might not be intelligent simply because I can't open up their heads and see if their brains are organic; the LTT is clearly sufficient to decide. Whether Stevan Harnad is an instance of a program or is human or is a cyborg from the Lesser Magellanic Cloud, I don't know. But I think I can conclude pretty easily, _from discussions on the net_, that Harnad is sentient. Biological inspection is not necessary. There are two possible answers to the second question. I shall show that only one of them is conceivable, which will put me in the same position as Harnad or nearly so. 1. A machine could achieve sentience by being directly programmed to be so. Well, if the only interface we are going to give it is the linguistic one, we are going to have to program it with enough knowledge to use the linguistic link for future learning - we are going to have to teach it language and install a complete set of past sensory experiences for it to draw on when deducing and inducing from its linguistic input. I think it is pretty clear that providing a machine with a full set of sensory experience up to the point of language fluency (8 human years worth, or so) is an impossible task. We simply won't ever know enough of anyone's experience to provide this. Not to mention the gargantuan task of data entry of all the experience and the equally gargantuan task of building all the right associations between the words and sensory experience. It's just not practical. 2. A machine could achieve sentience by being given the proper self-organizing properties (say a large and biologically accurate self-configuring neural network), a sufficiently rich set of inputs (videocam vision, microphone hearing, pressure-plate touch, and so on), and a sufficiently rich set of outputs (robot arms, mobility, speech generation and so on) Such a machine would only need to be given rudimentary, instinctive knowledge, some hardwired behaviors (such as jerking a limb away from an excessive heat source), pain, pleasure, and a few other capabilities, and it would pick up the rest on its own. Then, for the LTT, one isolates the machine from the judge and allows only communication via tty. This is the option I think might work. Of course, producing a 'tabula rasa' sentient being by means of physical labor and a 9 month manufacturing process is likely to remain more economical for some time to come. Dan Hankins " " -
dmocsny@uceng.UC.EDU (daniel mocsny) (04/09/89)
In article <16872@cup.portal.com>, dan-hankins@cup.portal.com (Daniel B Hankins) debates the nature of "artifact" with gilbert@cs.glasgow.ac.uk (Gilbert Cockton). Gilbert Cockton writes: > >Given a well-understood task, computer programs will out-perform humans. > >Given a poorly understood task, they will look almost as silly as the > >author of the abortive program. Daniel Hankins ripostes with examples of man-made systems that can solve poorly-understood problems. The discussion reminds me of Stephen Wolfram's discussion in his paper "Approaches to Complexity Engineering," which appeared in Physica D, 1985. In this paper, Wolfram contrasted traditional engineering design with the emerging art of complexity engineering. In a traditional artifact, the engineer proceeds from a detailed logical description of every part of a system and all its behaviors. The system, if successful, does what it is designed to do---nothing more and nothing less. The parts of the system interact with each other in tightly constrained, often linear, ways. Motions are usually periodic and synchronous. Failure in one part of the system often causes catastrophic failure of the entire system. The system can usually tolerate only a limited degree of environmental change. A complex system, on the other hand, consists of a large collection of individually simple parts, each having only a limited repertoire of possible behaviors. Each part interacts with its neighbors according to a fairly short list of typically nonlinear transition rules. The system as a whole exhibits enormously complex emergent behaviors, which the "designer" usually cannot predict in detail (since the system is computationally irreducible). The complex system can potentially exhibit other desired properties---e.g., robustness and adaptiveness. The trick in complexity engineering, of course, is to select the transition rules that yield the desired emergent behaviors. We are only just beginning to learn how to do this. If we succeed, then we may be able to take a huge chunk out of the "Logical Specification Problem." I.e., our limited ability to comprehend and manipulate lengthy logical specifications greatly restricts the complexity of our traditionally-engineered artifacts. The logical specification for a complex system of the type in the above paragraph is quite short in comparison to the behavior obtained. This is more in keeping with our ability to design things. Dan Mocsny dmocsny@uceng.uc.edu
lee@uhccux.uhcc.hawaii.edu (Greg Lee) (04/10/89)
From article <16873@cup.portal.com>, by dan-hankins@cup.portal.com (Daniel B Hankins): " >When I compile a program, assembly language with symbols is produced, " ... " The problem is with the representation relation, which the computer " does not embody. No representation, no symbols. A symbol that means " nothing is no symbol at all. So a label which is the target of a branch instruction does not represent anything, eh. Not even a location in the program? Are you under the impression that you are making sense here? Let me disabuse you. Look, I know what's coming next. Just as earlier we were treated to a distinction between understanding of the ordinary sort which a computer can display and "true" understanding with an essential subjective element, now you're going to say the things in an assembly language program aren't "true" symbols. There's some special human magic I invest in symbols when I write a program that compilers can never know. So you can spare us the usual mumbo-jumbo. Greg, lee@uhccux.uhcc.hawaii.edu
bwk@mbunix.mitre.org (Barry W. Kort) (04/11/89)
In article <16873@cup.portal.com> dan-hankins@cup.portal.com (Daniel B Hankins) writes: > A symbol that means nothing is no symbol at all. How about the mathematical symbols for zero and the null set? How about the ASCII symbols for SPACE and NULL? --Barry Kort
dan-hankins@cup.portal.com (Daniel B Hankins) (04/11/89)
In article <3701@uhccux.uhcc.hawaii.edu> lee@uhccux.uhcc.hawaii.edu (Greg Lee) writes: >So a label which is the target of a branch instruction does not represent >anything, eh. Not even a location in the program? Are you under the >impression that you are making sense here? Let me disabuse you. The operative question is, just whose label is it? Is it your label, or is it the computer's label. To you, a horse in a painting may be a symbol of virility. To the painter, it may have been merely an animal he happens to like (perhaps he owns a horse), and represents nothing. To the painter, it may not have been a symbol at all. The world is full of people making symbols (for themselves) out of things that are not, and of assigning meanings to symbols that never entered the symbol creator's mind. Symbolism is, to a large extent, private and subjective. >Look, I know what's coming next. Just as earlier we were treated to a >distinction between understanding of the ordinary sort which a computer >can display and "true" understanding with an essential subjective element, >now you're going to say the things in an assembly language program aren't >"true" symbols. There's some special human magic I invest in symbols when >I write a program that compilers can never know. So you can spare us the >usual mumbo-jumbo. No special magic, no mumbo-jumbo. Just an observation that what to you is a symbol of some thought-entity (a branch location) is to the computer merely another arrangement of voltages to be manipulated. To _you_, it's a symbol. To the computer, it's the object of discourse, and not a symbol at all. The use/mention distinction, again. Dan Hankins At one place was a Master who answered all questions by holding up one finger. One of his students, seeing this, began to emulate him. The Master had the student brought before him, and asked him the nature of the Buddha. When the student held up one finger the Master drew his sword and cut it off. The student screamed in pain and cried out, "Why did you do that?". The Master smiled and held up one finger. Then the student was enlightened. _ -Zen koan
gblee@maui.cs.ucla.edu (Geunbae Lee) (04/13/89)
In article <49015@linus.UUCP> bwk@mbunix (Barry Kort) writes: >In article <16873@cup.portal.com> dan-hankins@cup.portal.com >(Daniel B Hankins) writes: > > > A symbol that means nothing is no symbol at all. > >How about the mathematical symbols for zero and the null set? >How about the ASCII symbols for SPACE and NULL? > >--Barry Kort Do you really think that the mathematical symbols for zero and null set AND the ASCII symbols for space and null means NOTHING? In my opinion, they mean SOMETHING VERY IMPORTANT and FUNDAMENTAL !!!! -- Geunbae Lee AI lab, UCLA
bwk@mbunix.mitre.org (Barry W. Kort) (04/13/89)
In article <22885@shemp.CS.UCLA.EDU> gblee@cs.ucla.edu (Geunbae Lee) writes: > In article <49015@linus.UUCP> bwk@mbunix (Barry Kort) writes: > > In article <16873@cup.portal.com> dan-hankins@cup.portal.com > > (Daniel B Hankins) writes: > > > A symbol that means nothing is no symbol at all. > > How about the mathematical symbols for zero and the null set? > > How about the ASCII symbols for SPACE and NULL? > Do you really think that the mathematical symbols for zero and > null set AND the ASCII symbols for space and null means NOTHING? > In my opinion, they mean SOMETHING VERY IMPORTANT and FUNDAMENTAL !!!! Geunbae, you appear to be in violent agreement with me on this point. --Barry Kort
rayt@cognos.UUCP (R.) (04/14/89)
In article <49015@linus.UUCP> Barry Kort writes: >In article <16873@cup.portal.com> Daniel B Hankins writes: > > A symbol that means nothing is no symbol at all. >How about the mathematical symbols for zero and the null set? >How about the ASCII symbols for SPACE and NULL? I consider zero magnitude and a set with no elements to have meaning: both indicating the absence of a particular class of objects or properties. The latter two are interesting because they are the background from which the foreground gains its meaning, hence are meaningful as boundaries. Clearly, though, they can be given special meanings outside of this function. R. -- Ray Tigg | Cognos Incorporated | P.O. Box 9707 (613) 738-1338 x5013 | 3755 Riverside Dr. UUCP: rayt@cognos.uucp | Ottawa, Ontario CANADA K1G 3Z4
dan-hankins@cup.portal.com (Daniel B Hankins) (04/14/89)
In article <49015@linus.UUCP> bwk@mbunix.mitre.org (Barry W. Kort) writes: >>[me] A symbol that means nothing is no symbol at all. > >How about the mathematical symbols for zero and the null set? >How about the ASCII symbols for SPACE and NULL? Let me rephrase that sentence. It should read, "A symbol with no meaning is no symbol at all." The mathematical symbol '0' denotes a member of the set of numerals, a point on the number line, and so on. These are all things. The mathematical symbol {} denotes a member of the set of all sets, namely the one having no elements. This is a set and therefore also a thing. The empty set is still a set, just as an empty box is still a box. Dan Hankins
dan@acates.UUCP (Dan Ford) (04/14/89)
In article <16880@cup.portal.com> dan-hankins@cup.portal.com (Daniel B Hankins) writes: > 2. A machine could achieve sentience by being given the proper > self-organizing properties (say a large and biologically accurate > self-configuring neural network), a sufficiently rich set of inputs > (videocam vision, microphone hearing, pressure-plate touch, and so > on), and a sufficiently rich set of outputs (robot arms, mobility, > speech generation and so on) I see no reason why outputs would be necessary to achieve sentience. Of course without outputs outsiders would have a harder time determining whether the machine had achieved sentience. People who lack the ability to communicate with the outside world are no less sentient than those who can communicate. Perhaps the fact that a couple of the listed outputs (robot arms and mobility) are part of feedback systems, and thus also act as inputs, is what leads to the above statement. "Pure" outputs are needed to recognize sentience, not to achieve it. Dan Ford uunet!acates!dan "You may not have stolen any eggs, but I bet you've poached a few." Odd Bodkins
dan-hankins@cup.portal.com (Daniel B Hankins) (04/15/89)
In article <275@acates.UUCP> dan@acates.UUCP (Dan Ford) writes: >Perhaps the fact that a couple of the listed outputs (robot arms and >mobility) are part of feedback systems, and thus also act as inputs, is >what leads to the above statement. "Pure" outputs are needed to recognize >sentience, not to achieve it. This is what I had in mind. In order to achieve sentience, I feel (but am not convinced) that an entity needs to have rich interactions with its environment, for feedback purposes. And of course we need some kind of output in order to recognize the achieved sentience. Dan Hankins