From newshub.ccs.yorku.ca!ists!helios.physics.utoronto.ca!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!caen!nic.umass.edu!dime!orourke Tue Mar 24 09:56:47 EST 1992
Article 4551 of comp.ai.philosophy:
Xref: newshub.ccs.yorku.ca comp.ai.philosophy:4551 sci.philosophy.tech:2328
Path: newshub.ccs.yorku.ca!ists!helios.physics.utoronto.ca!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!caen!nic.umass.edu!dime!orourke
>From: orourke@unix1.cs.umass.edu (Joseph O'Rourke)
Newsgroups: comp.ai.philosophy,sci.philosophy.tech
Subject: Re: A rock implements every FSA
Keywords: Putnam's rock theorem
Message-ID: <45042@dime.cs.umass.edu>
Date: 18 Mar 92 12:25:08 GMT
References: <44855@dime.cs.umass.edu> <1992Mar17.014500.8635@bronze.ucs.indiana.edu> <44993@dime.cs.umass.edu> <1992Mar17.222238.9969@husc3.harvard.edu>
Sender: news@dime.cs.umass.edu
Reply-To: orourke@sophia.smith.edu (Joseph O'Rourke)
Followup-To: comp.ai.philosophy
Organization: Smith College, Northampton, MA, US
Lines: 31

In article <1992Mar17.222238.9969@husc3.harvard.edu> 
	zeleny@zariski.harvard.edu (Mikhail Zeleny) writes:

[in response to David Chalmers' critique of Putnam's rock theorem]:

 >I've said it once, I've said it a thousand times: whatever the laws that
 >guarantee the state-transitions of a FSA, the same laws guarantee the
 >state-transitions of a rock.  Since physical necessity is the same, so is
 >the counterfactual force.

I don't see how this blunts the force of David Chalmers' point, a point
which I misunderstood the first time around.  I think perhaps David
should not phrase his objection in terms of "counterfactuals," as
that term carries quite another connotation in the context of Putnam's book.
	His point is that the rock 'implements' a particular trace of
the FSA, a sequence of "table calls" as Putnam says.  Although Putnam
does not make this clear in his proof, he is arranging for the rock
to mirror a particluar sequence of state transitions that the FSA might
go through during some "run."  He can do this because he initially
assumes that the FSA has no inputs and no outputs.  So it only has only
one possible trace when it is run.
	He modifies this assumption after the proof, by saying that
I/O can be handled by imagining an FSA that, roughly, hallucinates
its input, and behaves as the original would if it were to receive
such and such an input.  But now the rock states are fixed to a
particular hallucinated input.  It is stretching the notion of
"implementation" beyond anything reasonable to say that this rock
implements the FSA:  rather it mirrors the trace of the FSA on a
particular input.
	By now I've put a lot of words in David Chalmer's mouth.  If
this is not his objection, then consider it my objection.


