Newsgroups: comp.ai.philosophy
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From: cam@castle.ed.ac.uk (Chris Malcolm)
Subject: Re: Minsky's new article (was: Roger Penro
References: <39d8g2$dlm@coli-gate.coli.uni-sb.de> <jqbCzG3K0.85K@netcom.com> <1994Nov18.134842.27593@oxvaxd>
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Organization: University of Edinburgh
Date: Fri, 18 Nov 1994 17:44:32 GMT
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In article <1994Nov18.134842.27593@oxvaxd> econrpae@vax.oxford.ac.uk writes:

>(2) In order for a creature to have mental state X, that creature must have
>certain quantum-physical properties

>Now (2) does indeed threaten AI. But physical and biological evidence is
>irrelevant to (2). The proper way to argue for (2) is by claiming that there
>are certain sort of problems which cannot be solved in polynomial time unless
>we use a quantum computer.

In his first book Penrose claimed that a certain natural
crytallisation solved a tiling problem which could not be solved
without look-ahead, thus demonstrating the existence of extremely
useful quantum computational properties which --- if the brain made
use of them --- would lift it far beyond the reach of plodding von
Neumann computers.  Unfortunately his argument rested on on the rather
unsteady "since I cannot imagine X after trying VERY hard then X
cannot exist" argument. By sheer bad luck someone else succeeded in
publishing in Sci Am how to imagine X (solve the crystallisation
tiling problem without look-ahead) within a year or two of the book's
publication.

It's a pretty savage arena, this philosophy of mind business.
-- 
Chris Malcolm    cam@uk.ac.ed.aifh          +44 (0)31 650 3085
Department of Artificial Intelligence,    Edinburgh University
5 Forrest Hill, Edinburgh, EH1 2QL, UK                DoD #205
"The mind reigns, but does not govern" -- Paul Valery
