Newsgroups: comp.ai.philosophy
Path: utzoo!utgpu!watserv1!watdragon!violet!cpshelley
From: cpshelley@violet.uwaterloo.ca (cameron shelley)
Subject: Re: Just Minds and Machines this time
Message-ID: <1991Jan27.185935.18038@watdragon.waterloo.edu>
Sender: daemon@watdragon.waterloo.edu (Owner of Many System Processes)
Organization: University of Waterloo
References: <11656.9101241836@s4.sys.uea.ac.uk> <1991Jan25.022026.12999@watdragon.waterloo.edu> <16510@venera.isi.edu>
Date: Sun, 27 Jan 91 18:59:35 GMT
Lines: 70

In article <16510@venera.isi.edu> smoliar@venera.isi.edu (Stephen Smoliar) writes:
[...]
>
>I want to pick up on this and perhaps try to assimilate it with Stuart
>Hampshire's recent article on Wittgenstein (actually his review of the
>new Monk biography) in THE NEW YORK REVIEW.  Hampshire offers what I feel
>is an excellent summary of the essence of the TRACTATUS:
>
>	According to the TRACTATUS the multiplicity of elements in
>	a sentence ought to be a picture of the multiplicity of
>	elements in a state of affairs.  The formal correspondence
>	secures for us the reference to a particular point in reality.
>
>To some extent, the idea that it makes sense to talk about such "a particular
>point in reality" at all was one of the major positions Wittgenstein chose to
>contest in his later work;  but I find it interesting that much of
>connectionism almost seems to have translated this idea of "a particular
>point in reality" into a point in some multidimensional energy landscape.
>What counts as robustness is nothing more than the observation that these
>landscapes tend to be sufficiently smooth that perturbation of a starting
>point will not severely disrupt its trajectory along this landscape.  Cam's
>observation that this is but one way of viewing what "error" might be is well
>taken;  and perhaps it obliges us to go back and think some more about
>appropriate metaphors for these points in "reality."
>
I'd like to think so.  The predominant model for connectionist architectures
seems to be thermodynamics, at least in networks that use relaxation
methods such as "simulated annealing" in which training is thought of
as lowering the 'temperature' of a system so that its 'energy' becomes
minimized.  Of course, in classical physics, nature does not make
'mistakes' (ie. be "ill-formed"), whereas it can at least be 'deformed'
in modern physics.  

>Let us suppose that we still have some sort of multidimensional space as a
>metaphor for reality;  but rather than filling it with an energy landscape,
>suppose we instead insert a linkage structure, sort of like a linear undirected
>graph, as a model of an agent's "knowledge" (whatever that may mean).  The
>reason I wish to appear to this metaphor is as an alternative to modeling
>reasoning in terms of the trajectory of a point in the space which seeks out
>an energy sink.  Think, instead, of accommodating a point in space by asking
>how that linkage structure might get flexed, or, perhaps expanded, in such a
>way that it ultimately "meets" that point;  that resulting "meeting" might then
>be regarded as an "interpretation" of that point.  Given sufficiently liberal
>laws of what you could do with the linkages, any given point would obviously
>be subject to multiple interpretations, which would mean it is not really a
>fixed "point in reality" (which, as I assumed above, was one of the problems
>Wittgenstein was trying to get away from).  From Cam's point of view, the
>question of whether or not the point is "well-formed" ultimately boils down
>to whether or not the linkages can be configured to "meet" it.
>
Hmmm.  An interesting notion!  Could you elabourate on "meet"?  If I
understand correctly, you mean the structure can be deformed by some
composition of adjustments applied to its parts.  This seems plausible
with the proviso that the entire structure need not be completely
connected (or am I missing something?).  The notion "ill-formed" would
be the requirement of an 'illegal' translation of the structure, while
"ill-transmitted" would be uncertainty about the point being met.
Would we have to know all possible translations of the structure in 
order to separate 'legal' from 'illegal'?  Complexity could then be
measured by the number of elementary translations and deformations
necessary to meet the point in question.  By then, the default (or
acquisition of) the structure becomes an issue...

				Cam

--
      Cameron Shelley        | "Absurdity, n.  A statement of belief
cpshelley@violet.waterloo.edu|  manifestly inconsistent with one's own
    Davis Centre Rm 2136     |  opinion."
 Phone (519) 885-1211 x3390  |				Ambrose Bierce
