[FOM] The Lucas-Penrose Thesis

Robbie Lindauer robblin at thetip.org
Sun Oct 1 16:01:25 EDT 2006

On Sep 29, 2006, at 2:51 PM, John McCarthy wrote:

>      Program: I can use any system you like, although mostly I
>      use a system based on a variant of ZF and descended from
>      1980s work of David McAllester.

It is almost certainly not true that the program can "use any system 
you like".  At least not any actual computer, and certainly not the 
traditional turing machine.  Different actual computers have different 

But remember,this proposal is not a contest, this proposal is, 
supposedly, a scientific hypothesis.

It says "Formalism X is the formalism of person P."  There is no room 
for peekaboo here.

This is Lucas' Obtuseness objection.  The mechanist OWES it to the 
scientific community to produce a particular algorithm as THE algorithm 
which is identical with the person in question.  The person doesn't 
need to deliver any such algorithm as a representation of his or her 

As long as one continues the obfuscation path, Lucas' argument wins 
out.  The (hypothetical) mechanist-scientist must be able to produce an 
(hypothetical) actual algorithm that is an (hypothetical) actual human 
otherwise the (hypothetical) proposal is hot air, akin to proposing 
that human DNA has a particular structure, but we can't ever say which.

Robbie Lindauer

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