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Article 4516 of comp.ai.philosophy:
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>From: chalmers@bronze.ucs.indiana.edu (David Chalmers)
Subject: Re: A rock implements every FSA
Message-ID: <1992Mar17.224156.9177@bronze.ucs.indiana.edu>
Organization: Indiana University
References: <44855@dime.cs.umass.edu> <1992Mar17.014500.8635@bronze.ucs.indiana.edu> <44993@dime.cs.umass.edu>
Date: Tue, 17 Mar 92 22:41:56 GMT

In article <44993@dime.cs.umass.edu> orourke@sophia.smith.edu (Joseph O'Rourke) writes:

>Putnam is well aware of the counterfactuals objection, and devotes pages
>96-105 of his book to refuting it.  But the refutation is curious.  He
>focuses exclusively on David Lewis's theory, which is perhaps not
>inappropriate since (a) Lewis wrote a paper in direct response to
>Putnam (a paper which I have not read), and (b) Lewis is Mr. Counterfactual
>if anyone is.

All this is irrelevant to my point.  On those pages, Putnam is concerned
with the question of the satisfaction of counterfactuals like "if
A had not happened, B would not have happened", and points out
that the truth-conditions for statements like these are problematic.
I'm concerned with the much more straightforward matter of making
sure that the implementation actually satisfies all the transition
relations in the state-table; e.g. such that if it is in state C,
it will transit to state D, and so on.  There's nothing problematic
about *these* counterfactuals, as C and D should have well-defined
sets of maximal states corresponding to them (if they were defined
at all, which they're not).

i.e. I'm not concerned, as Lewis is, with using counterfactuals to make
sure that certain conditions are met in backing the "A causes B"
statement.  I'm happy to accept Putnam's construal of causation here
as "B always follows A", but I'm concerned with making sure that *all* 
the causal statements are satisfied, not just those that actually come
up in a given sequence, like "if A then B", but all the others specified
by the machine table, like "if C then D".  So Lewis' and my objections
have little to do with each other, and Putnam's response to Lewis
is irrelevant here.

Incidentally Lewis's published response to Putnam ("Putnam's Paradox",
in Australasian Journal of Philosophy circa 1984), was not on this
topic at all, but rather on Putnam's argument about reference and
realism.

-- 
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."


