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>From: tom@csustan.csustan.edu (Tom Carter)
Newsgroups: comp.ai.philosophy,sci.philosophy.tech
Subject: Re: A rock implements every FSA
Summary: Putnam's theorem is bunk :-)
Message-ID: <1992Mar18.101522.20017@csustan.csustan.edu>
Date: 18 Mar 92 10:15:22 GMT
References: <1992Mar17.224156.9177@bronze.ucs.indiana.edu> <45005@dime.cs.umass.edu> <1992Mar18.014416.9980@husc3.harvard.edu>
Organization: CSU Stanislaus
Lines: 36

Concerning Putnam's (alleged) theorem about `FSA' and rocks . . .

(There are two of these posts -- this one more or less short and snotty,
the other less short :-)


What is wrong with the following theorem/proof?

Theorem:  Any large rock is a realization of (functionally equivalent to)
a car.

Proof:  `Large' is of course a technical term.  By `large', in this context,
   I mean a rock whose minimum linear dimension is at least 20 billion
   angstroms, a property which is actually satisfied by many real rocks
   within our solar system, and in fact by many rocks on the surface of the
   earth.  A car, of course, is characterized as a device on or in which a
   person can sit.

   Now, the average person is at least 10 billion angstroms in at least
   one linear dimension, and typically no more than 20 billion angstroms
   in  any linear dimension, and thus can easily sit on a large rock.
   This shows that any large rock is a realization of a car.

   Some automotive engineers may observe that many cars have wheels, and can
   move from place to place carrying the person.  This sort of restriction
   on the notion of `car' changes the situation so much that my theorem has
   no hope of continuing to hold.  However, we can still carry out a version
   of our proof as long as we are willing to paint wheels on our rock, and
   thus talk about a rock-with-wheels, and observe that as long as the car
   with wheels does not move, the theorem still applies.

Discussion:  This theorem has the obvious dire consequences for those
   who insist that the function of a car is somehow different from
   its behavior while sitting there in my driveway!

Tom Carter                       tom@csustan.csustan.edu


