From newshub.ccs.yorku.ca!ists!helios.physics.utoronto.ca!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!bronze!chalmers Sun Dec  1 13:06:31 EST 1991
Article 1739 of comp.ai.philosophy:
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>From: chalmers@bronze.ucs.indiana.edu (David Chalmers)
Subject: Re: Dennett on Edelman--what a total loss
Message-ID: <1991Nov29.040039.19327@bronze.ucs.indiana.edu>
Organization: Indiana University
References: <5734@skye.ed.ac.uk> <1991Nov28.051621.24327@bronze.ucs.indiana.edu> <5743@skye.ed.ac.uk>
Date: Fri, 29 Nov 91 04:00:39 GMT
Lines: 48

In article <5743@skye.ed.ac.uk> jeff@aiai.UUCP (Jeff Dalton) writes:

>In article <1991Nov28.051621.24327@bronze.ucs.indiana.edu> chalmers@bronze.ucs.indiana.edu (David Chalmers) writes:
>>In article <5734@skye.ed.ac.uk> jeff@aiai.UUCP (Jeff Dalton) writes:
>>
>>>In article <1991Nov27.031545.11235@bronze.ucs.indiana.edu> chalmers@bronze.ucs.indiana.edu (David Chalmers) writes:

>>>>He comes close to saddling AI researchers with the ridiculously strong
>>>>claim that "the brain is a Turing machine" (a claim that I note has
>>>>been bandied about a number of times in this newsgroup, almost always
>>>>by anti-AI proponents looking for straw figures). 
>>>
>>>Really, I thought they were arguing that artificial intelligences
>>>on computers (_not_ brains) were FSAs (_not_ Turing Machines).
>>
>>The quantifier was existential, not universal.
>
>So?

So you can't refute an existentially quantified statement ("has been
bandied about a number of times") by pointing to the existence of
other discussions.

>I do not agree with your "almost always", though perhaps I
>should retract the "not brains".  (I thought the double disagreement
>was more amusing.  Sorry if it confused.)

Pointing to the existence of discussions about other claims is equally
irrelevant to refuting the "almost always" claim; and your negations
did not confuse.  But moving from metametadiscussion to metadiscussion...

>Moreover, it seems to
>be the pro-AI side that is claiming all of the necessary properties
>of brains can be captured by TMs.

Indeed.  I agree with this claim myself.  But it this is a very
different claim from the claim that "the brain is a Turing Machine".
I see the latter claim far more often from opponents of AI putting
words into AI-supporters' mouths.  (Along with similar claims, such
as "the brain is a digital computer", "the mind is a program", and
so on.  Perhaps all of these have been held by some AI proponents
at some time -- Zenon Pylyshyn would be a good bet -- but all are
far stronger claims than what is necessary for the success of AI.)

-- 
Dave Chalmers                            (dave@cogsci.indiana.edu)      
Center for Research on Concepts and Cognition, Indiana University.
"It is not the least charm of a theory that it is refutable."


