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Article 4787 of comp.ai.philosophy:
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>From: chalmers@bronze.ucs.indiana.edu (David Chalmers)
Subject: Re: On functionalism and implementation
Message-ID: <1992Mar29.010616.27439@bronze.ucs.indiana.edu>
Organization: Indiana University
References: <1992Mar27.184244.7511@u.washington.edu>
Date: Sun, 29 Mar 92 01:06:16 GMT

In article <1992Mar27.184244.7511@u.washington.edu> forbis@milton.u.washington.edu (Gary Forbis) writes:

>I'm pretty sure that more than a mapping between inputs and current states to
>next states is necessary for particular implementations of a FSA to be 
>functionally equivalent.
>
>Consider a John Deere tractor and a farmer who uses one but is looking for
>a replacement.  Here I am trying to sell him an International Harvester and
>I say it is functionally equivalent.  I certainly don't mean that one could
>find a mapping between input and current state to next state of both devices.
>There is something about the way in which a functionally equivalent system
>is implemented that lay people usually refer to.

That's related to the point about constraints on mapping inputs and
outputs, which Putnam himself endorses.  For a system to be functionally
equivalent to a tractor, it has to produce output of a very constrained
kind.  There's much more freedom about mapping internal states.

-- 
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."


