rlw@wxlvax.UUCP (Richard L. Wexelblat) (05/15/84)
Here is a thought which a friend and I have been kicking around for a while (the friend is a professor of philosophy at Penn): It seems that it is IMPOSSIBLE to ever build a computer that can truly perceive as a human being does, unless we radically change our ideas about how perception is carried out. The reason for this is that we humans have very little difficulty identifying objects as the same across time, even when all the features of that object change (including temporal and spatial ones). Computers, on the other hand, are being built to identify objects by feature-sets. But no set of features is ever enough to assure cross-time identification of objects. I accept that this idea may be completely wrong. As I said, it's just something that we have been batting around. Now I would like to solicit opinions of others. All ideas will be considered. All references to literature will be appreciated. Feel free to reply by mail or on the net. Just be aware that I don't log on very often, so if I don't answer for a while, I'm not snubbing you. --Alan Wexelblat (for himself and Izchak Miller) (currently appearing at: ...decvax!ittvax!wlxvax!rlw Please put "For Alan" in all mail headers.)
norm@ariel.UUCP (05/16/84)
The computer needs to be able to distinguish between "metaphysically identical" and "essentially the same". This distinction is at the root of an old (2500 years?) Greek ship problem: Regarding Greeks ship problem: When a worn board is replaced by a new board, the ship is changed, but it is the same ship. The difference leaves the ship essentially the same but not identically the same. If all the boards of a ship are replaced one by one until the ship is entirely redone with new boards, it is still the same ship (essentially). Now, if all the old boards that had been removed were put together again in their original configuration so as to duplicate the new-board ship, would the new old-board ship be iden- tically or essentially the same as the original old-board ship? Assume nailless construction techniques were used thruout, and assume all boards always fit perfectly the same way every time. We now have two ships that are essentially the same as the original ship, but, I maintain, neither ship is identical to the original ship. The original ship's identity was not preserved, although its identity was left sufficiently unchanged so as to preserve the ship's essence. The ship put together with the previously-removed old boards is not identically the same as the original old-board ship either, no matter how carefully it is put together. It too is only essentially the same as the original ship. A colleague suggested that 'essence' in this case was contextual, and I tend to agree with him. Actually, even if the Greeks left the original ship alone, the ship's identity would change from one instant to the next. Even while remaining essentially the same, the fact that the ship exists in the context of (and in relation to) a changing universe is enough to vary the ship's identity from moment to mo- ment. The constant changes in the ship's characteristics are admittedly very subtle, and do not change the essential capacity/functionality/identity of the ship. Minute changes in a ships identity have 'essentially' no impact. Only a change sufficiently large (such as a small hole in the hull) have an essential impact. "Essence" has historically been considered metaphysical. In her "Introduction to Objectivist Epistemology" (see your local bookstore) Ayn Rand identified essence as epistemological rather than metaphysical. The implications of this identification are profound, and more than I want to get into in this article. Philosopher Leonard Peikoff's article "The Analytic-Synthetic Dichotomy", in the back of the newer editions of Rand's Intro to Obj Epist, shows how crucial the distinction between essence-as-metaphysical and essence-as-epistemological really is. Read Rand's book and see why the computer would have to make the same distinc- tion. That distinction, however, has to be made on the CONCEPTUAL level. I think Rand's discussion of concept-formation will probably convince you that it will be quite some time before man-made machinery is up to that... Norm Andrews, AT+T Information Systems (201)834-3685 vax135!ariel!norm
rosen@gloria.UUCP (Jay Rosenberg) (05/16/84)
> Here is a thought which a friend and I have been kicking around for a while > (the friend is a professor of philosophy at Penn): > > It seems that it is IMPOSSIBLE to ever build a computer that can truly > perceive as a human being does, unless we radically change our ideas > about how perception is carried out. > > The reason for this is that we humans have very little difficulty > identifying objects as the same across time, even when all the features of > that object change (including temporal and spatial ones). Computers, > on the other hand, are being built to identify objects by feature-sets. But > no set of features is ever enough to assure cross-time identification of > objects. Just a few quick comments, 1) The author seems to use perceive as visual perception. It can not be a prerequisite for intelligence due to all the counter examples in the human race. Not every human has sight, so we should be able to get intelligence from various types of inputs. 2) Since humans CAN do it is the evidence that OTHER systems can do it. 3) The major assumption is that the only way a computer can identify objects is by having static "feature-sets" that are from the object alone, without having additional information, but why have that restriction? First, all features don't change at once, your grandmother doesn't all of a sudden have the features of a desk. Second, the processor can/must change with the enviornment as well as the object in question. Third, the context plays a very important role in the recognition of of an object. Functionality of the object is cruical. Remindings from previous interactions with that object, and so on. The point is that clearly a static list of what features objects must have and what features are optional is not enough. Yet there is no reason to believe that this is the only way computers can represent objects. The points here come from many sources, and have their origin from such people as Marvin Minsky and Roger Schank among others. There is alot of literature out there.
merlyn@sequent.UUCP (05/16/84)
> From: rlw@wxlvax.UUCP > Message-ID: <277@wxlvax.UUCP> > Date: Tue, 15-May-84 23:33:31 PDT > > It seems that it is IMPOSSIBLE to ever build a computer that can truly > perceive as a human being does, unless we radically change our ideas > about how perception is carried out. > > The reason for this is that we humans have very little difficulty > identifying objects as the same across time, even when all the features of > that object change (including temporal and spatial ones). Computers, > on the other hand, are being built to identify objects by feature-sets. But > no set of features is ever enough to assure cross-time identification of > objects. I dunno about that. Think of the many times you have heard "is that the same Mary Jones I went to high school with? She's not the same person at all!" Now, obviously, Mary Jones is the same person (or the whole statement is false). Yet, by some method of *distinction* (key word!), the person is distinguishing Mary Jones @ now from Mary Jones @ high school. Distinctions seem to be the key. I suggest that what we are doing as human beings in PERCEIVING is merely drawing a line of distinction between things that are in the set, and things that are out of the set. For example, we distinguish UP from DOWN, LEFT from RIGHT, WRONG from RIGHT (bad pun!). So, in the case of Mary Jones, *enough* (another keyword) similar distinctions exists for Mary Jones, even invariant of time and space, that she gets to retain her identity (for most people). For the person uttering the statement above, however, *not enough* of the distinctions are consistent, hence the statement of her not being who she was. I think (this is guessing now, but based on observation [ARRGH... more perceptions!]) that the act of perception is based on triggering ENOUGH DISTINCTIONS to warrant a match with past data. Data, by the way, is all stored as distinctions as well. So if eyes, face, name, and approximate age match for Mary Jones, the inference is that all other distinctions made for her (such as favorite music), as well as for high-school people, girls, and so on, all fit identically. My evidence for this MODEL (also a keyword) [that all we are are the distinguishers of sensory input] is that I work with people to produce breakthrough (beyond predictable and explainable) results. I operate with them like life is merely an interpretation, a collection of distinctions. People make distinctions unconciously that are counter to their goals. I simply have them remove distinctions that are barriers. Poof. (That's a side topic by itself... I just said it to describe the source of my evidence.) MODEL is a keyword to demonstrate that this, AGAIN, is merely a distinction that *I* am drawing. As far as I can tell, everything I can possibly recognize is based on my own interpretations and labling and distinctions I drew in the past, but that's also a model. It could be just as likely that a little bird whispers in my ear to tell me that Mary Jones is standing out there, and that her favorite music is Rock, but that model makes it much harder to produce breakthrough results. I"ll stick with one that works to produce my own intentions. Sorry for the length... this area is one of my favorite topics. I'll answer mail, but I'd prefer news for discussions of interest to more than just you and me. -- A particularly personal and original observation from the thought-stream of Randal L. ("distinguished observer") Schwartz, esq. (merlyn@sequent.UUCP) (Official Legendary Sorcerer of the 1984 Summer Olympics) Sequent Computer Systems, Inc. (503)626-5700 (sequent = 1/quosine) UUCP: {decwrl,ogcvax,pur-ee,rocks34,shell,unisoft,vax135,verdix}!sequent!merlyn Original Material (C) 1984 by Randal L. Schwartz [ALL RIGHTS RESERVED]
simon@psuvax.UUCP (Janos Simon) (05/21/84)
[] The philosophical discussion seems to reveal the basic fallacy of the original argument (Computers cannot possibly ...), namely, WHAT is it that we want computers to do? The original submission basically said "This is how we humans would act. Computers are being programmed today to simulate such behavior using very restricted techniques. Therefore no such simulation can possibly exist." Some very learned submissions showed that there is wide disagreement in defining what we mean by "sameness" - in fact this is a fundamental question of philosophy. Nevertheless, each of the competing explanations could be mechanized - perhaps at prohibitive cost. js