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From: pindor@gpu.utcc.utoronto.ca (Andrzej Pindor)
Subject: Re: Lucas & Penrose's use of Godel
Message-ID: <DBq2tM.CoB@gpu.utcc.utoronto.ca>
Organization: UTCC Public Access
References: <DBD1Kp.21A@gpu.utcc.utoronto.ca> <3u36qt$lak@netnews.upenn.edu> <DBo9C0.B0B@gpu.utcc.utoronto.ca> <3u47f7$o9v@netnews.upenn.edu>
Date: Fri, 14 Jul 1995 20:12:58 GMT
Lines: 74
Xref: glinda.oz.cs.cmu.edu comp.ai.philosophy:30204 sci.logic:12418

In article <3u47f7$o9v@netnews.upenn.edu>,
Matthew P Wiener <weemba@sagi.wistar.upenn.edu> wrote:
>In article <DBo9C0.B0B@gpu.utcc.utoronto.ca>, pindor@gpu (Andrzej Pindor) writes:
>>In article <3u36qt$lak@netnews.upenn.edu>,
>>Matthew P Wiener <weemba@sagi.wistar.upenn.edu> wrote:
>>>In article <DBM7xq.H5o@gpu.utcc.utoronto.ca>, pindor@gpu (Andrzej Pindor) writes:
>>>>In article <3u0ftu$44@netnews.upenn.edu>,
>>>>Matthew P Wiener <weemba@sagi.wistar.upenn.edu> wrote:
>>>>>In article <DBKGHJ.G5n@gpu.utcc.utoronto.ca>, pindor@gpu (Andrzej Pindor) writes:
>>>>>>You are right, this is the question of interest. Now, are you
>>>>>>claiming that chemical processes (and immunological infulences)
>>>>>>cannot be modelled digitally? Perhaps Goedel proved this?
>
>>>>>They can be modelled up to a point.  [...]
>
>>>>What reasons (except ideology) do you have to think that modelling
>>>>"up to this point" is not enough?
>
>>>The Lucas/Penrose argument.  What do you think?
>
>>I think that you are begging the question then.
>
>Not in the least.  YOU are, if your best argument against L/P is to
>say--"WHAT, YOU'RE USING L/P--WHY, THAT'S BEGGING THE QUESTION".
>
>>>>If you are going to fall onto non-computability at QM level, why
>>>>not to say this outright instead of setting up a smoke screen of
>>>>"chemical processes (and immunological influences)"?
>
>>>It's not a smokescreen.  We already know experimentally that the simple
>>>digital neuron model of mind is false.
>
>>Are we discussing correctness of a particular model of the mind
>>(simple digital neuron or like)
>
>I pointed out the obvious incorrectness of that to someone on the side,
>by way of known neurobiology.
>
You are either unable to admit that that you goofed, or you are completely 
confused - the "incorrectness" which you point out is a real one only if,
by virtue of alleged L/P argument, you claim that you cannot model chemical 
effects etc. by digital means in signifficant detail. So it boils down to
the alleged argument "in principle".

>>				 or a impossibility to model mind
>>digitally in principle?
>
>That is a different question.
>
>>			 Talk of chemical processes and like is a
>>smokescreen if in reality you are after the principle irrelevent of
>>the model.
>
>YOU mixed the two up, when you asked what makes me suspect--considering
>that we can digitally simulate some but not all aspects of chemistry--
>that the relevant neurochemistry will be in the non-simulable class.

See above.
In fact I have in an earlier posting pointed out that the Penrose's argument
(about inability of a machine to exceed a certain Goedelian limit) applies only
to an isolated machine. A machine situated in the real world (since 
mathematicians are situated in the real world, there is no reason to deny it 
to a machine) has no fixed Goedel limit. It can use input from the real world
to modify its axioms, enlarge them and hence move up from a formal system
which describes it at any given stage.
>-- 
>-Matthew P Wiener (weemba@sagi.wistar.upenn.edu)

Andrzej
-- 
Andrzej Pindor                        The foolish reject what they see and 
University of Toronto                 not what they think; the wise reject
Instructional and Research Computing  what they think and not what they see.
pindor@gpu.utcc.utoronto.ca                           Huang Po
