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Article 3524 of comp.ai.philosophy:
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>From: chalmers@bronze.ucs.indiana.edu (David Chalmers)
Subject: Re: Strong AI and panpsychism
Message-ID: <1992Feb6.053810.22191@bronze.ucs.indiana.edu>
Organization: Indiana University
References: <1992Feb5.005813.6383@nuscc.nus.sg> <1992Feb5.020733.21580@bronze.ucs.indiana.edu> <1992Feb5.185805.15433@psych.toronto.edu>
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Date: Thu, 6 Feb 92 05:38:10 GMT
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In article <1992Feb5.185805.15433@psych.toronto.edu> michael@psych.toronto.edu (Michael Gemar) writes:

>Is there any independent principled reason for not allowing time-dependent
>definitions, or are they ruled out merely so that the above situation is
>not a problem for functionalism?

Firstly, there's nothing wrong with modifying one's theses in order to
take account of potential counterexamples.  It happens all the time.
Secondly, I very much doubt that any functionalist ever intended
time-varying states to count as state-realizations.

Still, Putnam doesn't actually need time-varying states for the result
to go through, on the assumption that any object has an (implicit
or explicit) "clock" built into it, that ensures that it is in different
states at different times.  But the states that appear are nevertheless
highly gerrymandered.

I haven't examined Putnam's proof as closely as I should have, but it's
not at all clear to me that it establishes that any object implements
any FSA in the strong sense of not just getting actual but counterfactual
state-transitions right; and in particular getting the transitions upon
counterfactual inputs right.  If someone has a demonstration of this
I'd like to see it.  Putnam's proof doesn't provide this, and I suspect
that it may not hold up.

Finally, I think it's reasonable to require that states are what might
be called "causally efficacious" states, i.e. such that the property of
being in the state is capable of doing causal work, and not just within
an incestuous circle of related gerrymandered states; so they can be
hooked up to potentially cause simple actions in the environment for
instance (obviously, this is closely related to the last objection).
Pure time-varying states may not satisfy this, although Putnam's
gerrymandered clocked states may, under certain assumptions.

I don't have a definitive line on this.  I'm not certain that
restrictions on allowable states are needed, but if they are, I
suspect that they will be motivated by reflecting on our reasons for
thinking that a clock doesn't *really* implement an arbitrary FSA,
and fixing the definition of "implementation" accordingly.

-- 
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."


