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From: jamie@cs.sfu.ca (Jamie Andrews)
Subject: Re: Godel, Lucas, Penrose, and Putnam
Message-ID: <1994Dec23.190456.21538@cs.sfu.ca>
Organization: Faculty of Applied Science, Simon Fraser University
References: <3ddp99$tc@usenet.ucs.indiana.edu>
Date: Fri, 23 Dec 1994 19:04:56 GMT
Lines: 25
Xref: glinda.oz.cs.cmu.edu comp.ai.philosophy:24037 sci.logic:9182

In article <3ddp99$tc@usenet.ucs.indiana.edu>,
David Chalmers <chalmers@bronze.ucs.indiana.edu> wrote:
>Penrose's second argument proceeds, in essence, by saying "suppose I *am*
>formal system F", and then arguing that with this assumption in place, he
>can see the truth of statements that are beyond F's powers, even if F is
>supplemented by the assumption that it is F.  Let F' be the system derived
>by supplementing F with the assumption that it is F.

     Isn't this where the flaw lies?  If F' believes that it is
F, then it's wrong.  It's not F, it's F'.  Thus F' is
inconsistent.  I haven't read the book, and I'm not sure what is
meant by a system "knowing it is" some system, so I may be missing
something.

     But a deeper flaw may have to do with the idea of assuming
that a person's *reasoning* is one static formal system.  Once
we get into discussions about learning new assumptions, we've
moved the goalposts and have to talk about the person's
*learning* method as a static formal system.

     Just my foolish $0.02...

--Jamie.
  jamie@cs.sfu.ca
"Could you do the egg bacon spam and sausage without the spam then?"
