[comp.ai.digest] AI, science, and pseudo-science

mckee@CORWIN.CCS.NORTHEASTERN.EDU (07/22/87)

In AIlist Digest v5 #171, July 6, 1987, Don Norman
	<norman%ics@sdcsvax.ucsd.edu> wrote:
> [Here's why] many of us otherwise friendly folks in the sciences that
> neighbor AI [are] frustrated with AI's casual attitude toward theory:
> AI is not a science and its practitioners are woefuly untutored in
> scientific method."
	[ 15 lines deleted ]
> AI worries a lot about methods and techniques, with many books and
> articles devoted to these issues.  But by methods and techniques I
> mean such topics as the representation of knowledge, logic,
> programming, control structures, etc.  None of this method includes
> anything about content.  And there is the flaw: nobody in the field of
> Artificial Intelligence speaks of what it means to study intelligence,
> of what scientific methods are appropriate, what emprical methods are
> relevant, what theories mean, and how they are to be tested.  All the
> other sciences worry a lot about these issues, about methodology,
> about the meaning of theory and what the appropriate data collection
> methods might be.  AI is not a science in this sense of the word.
	[ 22 more lines deleted ]

I think he's found an issue of critical importance here, so I'm going
to pull it out of context even further and repeat it again:

"nobody in the field of Artificial Intelligence speaks of what it means
to *study* intelligence" (my emphasis).

No wonder those of us outside the field have trouble figuring out
what AI is really about.  My impression is that AI researchers try
to study intelligence by building artifacts that will make a convincing
show of intelligent behavior.  This might be why books on AI methods are all
about sophisticated representations and fancy program structures -
they're techniques of building more complex (hopefully more intelligent)
programs.  But this is nearsighted.  Intelligence is the *difference*
between unintelligent and intelligent behavior. The study of intelligence
begins when the programming stops.  And on what to do then, the AI textbooks
are silent.
	Now I don't want to spend time talking about the consequences
of this failure, Don did that much better than I can.  (However, I can't
resist throwing in my excuse: programming is fun; science is hard, often
boring, work.  Science is far more rewarding, though.) What I'm going to
discuss in the rest of this note stems from his remark that AI workers
are "woefully untutored in scientific method".  Assuming for the purposes
of discussion that we know enough about intelligence to make principled
distinctions between it and stupidity (counterintelligence?), what would
the scientific study of intelligence look like?

One way of answering this question is to look at some of the enterprises
that claim to be scientific, but aren't.  The main distinction in the
list below is between those fields that are unarguably sciences, and those
that fail to be scientific in one way or another.  True science, the authentic,
natural sciences, are ones like astronomy, geology, biology, physics, or
chemistry.  False sciences are harder to characterize, but here goes:

Here's a list of examples of different claimants to the name "science";
mostly impostors, all of them can be called "quasi-sciences".  By looking
at them, we can gain some sense of what qualities are necessary for
real sciences, since the quasi-sciences don't have them.

* Fraudulent sciences: Creation Science, Lysenkoism, Scientology
	(the most generous thing I can say about these is that they
	 appear to proceed by trusting exceptional, one-of-a-kind
	 reports, and denying persistent, repeated, quantitative,
	 skeptical observations.  In rhetoric this is called "appeal
	 to authority.")

* Trivial sciences: Clairol Science, barbeque science, accelerator science
	(Clairol Science has discovered a new way to make your
	 hair silkier and more full-bodied.  Barbeque science has
	 conclusively determined that mesquite smoke is superior to
	 hickory smoke. We need to build the superconducting supercollider
	 so America won't fall behind in accelerator science.)

* Semi-sciences: Theoretical Physics, Descriptive Linguistics
	(complementary halves of their respective fields.)

* Interdisciplinary Sciences: Materials Science, Neuroscience
	(characterized by their subject matter not yielding coherently
	 to any single experimental technique or theoretical paradigm.)

* Artifact Sciences: Economics, Political Science, Anthropology
	(Herbert Simon's "sciences of the artificial" - these study artifacts
	 of human society - without civilization, they wouldn't exist.
	 However, civilization is big and complex enough that techniques
	 developed to deal with natural phenomena give useful insights.)

* Synthetic Sciences: Mathematics, Computer Science
	(These study the consequences of small sets of fundamental concepts.
	 Mathematics under Russell&Whitehead and Bourbaki has been "nothing
	 but" an incredibly vast and elegant elaboration of set theory,
	 while [I claim with a certain trepidation] that the fundamental
	 basis of the scientific part of computer science lies in the
	 elaboration of the consequences of the notion of an algorithm.)

The authentic, natural sciences, on the other hand, are the body of analytic,
experimental studies of phenomena that go on whether or not the experimenter
is there to observe them, [philosophers can complain about "naive realism" --
I'll confess to the realism, but not not the naivete] and the results,
conclusions, and theoretical relations that tie the studies together.
The key concepts here are "experimental" and "objective".  If a researcher
(or a team of them) isn't doing experiments on some external phenomenon,
then it ain't real science.
	What do you get from real science? Reality. Not wishful thinking,
not hallucinations, not mythology, not common sense. (Strictly speaking,
what you get is the most compact model of reality consistent with the
most reliable, most detailed, widest ranging set of observations.)
Uncommon sense.
	What you don't get is completeness, or even closure.  First of all,
there's too much knowledge, as anyone with a Ph.D. in a natural science will
tell you.  Second of all, the universe isn't closed under observation: there's
always more detail to examined, further frontiers to be explored, greater
complexities to be explained.  And most exciting of all, there's the
possibility of revolution - that a new model will explain more data,
resolve old inconsistencies, or be statable more succinctly, hopefully
all at once.
	The natural sciences generate an interconnected web of explanations
that should contain a place for AI, if AI is a science.  It's in this
explanatory web that people claim to see the bugaboo of reductionism
(without which no discussion of scientific method would be complete).
Stripped of the argumentative mumbo-jumbo that keeps philosophers in business,
a reductionist would claim that a pile of parts on the floor is equivalent to
an assembled machine, while a holist would claim that the parts are irrelevant
to any description of the machine.  Both views are incomplete, but there is
indeed an ordering by "is explained in terms of" that reductionists
have grabbed onto.  Because it's only a partial ordering, I'd like to borrow
a term from evolutionary biology and suggest that scientific knowledge has
the same kind of familial, clade structure as do charts of the genetic
relations among organisms.  Reading "<--" as "is used to explain", we have

One path through a Cladistic epistemology:
        Particle Physics <--
         Condensed-matter physics <--
          Quantum Chemistry <--
           Organic Chemistry <--
            Molecular Biology/Genetics <--
             Developmental Biology <--
              Neuroscience <--
               Ethology <--
                Psychology <--
                 Cognitive Science <--
                  Mathematics

I would put intelligence in at the same level as mathematics.  Congratulations!
Scientific AI would be among the most complex of sciences.  However,
in reality the picture isn't this clean.  Aside from those sciences that
aren't in a direct explanatory line to intelligence, there are shortcuts
among levels due to the logic of experimental science, that makes it possible
to do things like manipulate genetic structure and get a behavioral result.

But this note is already too long to go into this further, and I've barely
alluded to the formal role of the hypothesis.

Hope this helps,
	- George McKee
	  College of Computer Science
	  Northeastern University, Boston 02115
CSnet: mckee@Corwin.CCS.Northeastern.EDU
Phone: (617) 437-5204
Usenet: in New England, it's not unusual to have to say
		"can't get there from hroror2

gilbert@hci.hw.ac.UK (Gilbert Cockton) (08/05/87)

In article <8707270710.AA05885@ucbvax.Berkeley.EDU>
mckee@CORWIN.CCS.NORTHEASTERN.EDU writes:
 a lot, but his go at describing types of not-quite-sciences is
 interesting. For me, AI should be one of the
>
>* Interdisciplinary Sciences: Materials Science, Neuroscience
>	(characterized by their subject matter not yielding coherently
>	 to any single experimental technique or theoretical paradigm.)
>
My criticism of AI is that most of the workers I meet are pretty
ignorant of the CRITICAL TRADITIONS of ESTABLISHED disciplines which
can say much  about AI's supposed object of study. When AI folk do stop
hacking (LISP, algebra or logic - it makes no difference, logic finger
and algebra wrist are just as bad as the well known 'computer-bum'),
they may do so only to raid a few concepts and 'facts' from some
discipline, and then go and abuse them out of sight of the folk who
originally developed them and understand their context and deductive
limitations.  What some of them do to English is even worse :-)

>(However, I can't resist throwing in my excuse: programming is fun;
> science is hard, often boring, work.  Science is far more rewarding, though.) 

I think the nail's been hit squarely on the head, but to programming we
should add amateur philosophy and idealist logic/algebra as other fun
pasttimes pursued instead of hard, critical, rigorous argument. I think
the major turn-off of AI work can be summed up as a complete lack of
candid scholarship. The same is unfortunately true for much
applications-driven research in computing. Without reining in AI (or
computer applications research) under proper disciplines, I can't
really see any prospect for workers developing their critical faculties
up to the highest standards of established disciplines.

NB - yes there are uncritical, unimaginative automata and disreputable
charlatans in all disciplines. But these sorts are not the type who
make a DISCIPLINE. AI seems to have few folk who do want it to be a
discipline.
-- 
   Gilbert Cockton, Scottish HCI Centre, Ben Line Building, Edinburgh, EH1 1TN
   JANET:  gilbert@uk.ac.hw.aimmi    ARPA:   gilbert%aimmi.hw.ac.uk@cs.ucl.ac.uk
		UUCP:	..!{backbone}!aimmi.hw.ac.uk!gilbert

andrew@trlamct.OZ.AU (Andrew Jennings) (08/15/87)

In article <108@glenlivet.hci.hw.ac.uk>, gilbert@hci.hw.ac.UK
(Gilbert Cockton) writes:
> 
> My criticism of AI is that most of the workers I meet are pretty
> ignorant of the CRITICAL TRADITIONS of ESTABLISHED disciplines which
> can say much  about AI's supposed object of study. When AI folk do stop
> hacking (LISP, algebra or logic - it makes no difference, logic finger
> and algebra wrist are just as bad as the well known 'computer-bum'),
> they may do so only to raid a few concepts and 'facts' from some
> discipline, and then go and abuse them out of sight of the folk who
> originally developed them and understand their context and deductive
> limitations.  What some of them do to English is even worse :-)
> -- 

I am afraid I cannot let this pass. It almost appears as if you view
programming as charlatan in itself ! Suffice it to say that if we
view AI as an empirical search then we have some definite criteria : either the
program works or it does not. 

Sure I'm in favour of CRITICAL thought and CRITICAL appraisal of work in AI :
its just that I don't want to get buried in a pile of useless Lemmas (no doubt
generated by you and your accomplices).

Why can't you realise the simple truth : a discipline goes through STAGES of
development. First the empirical paradigm dominates, then the engineering 
paradigm and last of all the theoreticians replete with armchairs.




-- 
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Andrew Jennings                             Telecom Australia Research Labs