Newsgroups: comp.ai.philosophy,comp.ai,comp.robotics,comp.cog-eng,sci.cognitive,sci.psychology
Path: cantaloupe.srv.cs.cmu.edu!das-news2.harvard.edu!news2.near.net!news.mathworks.com!gatech!swrinde!cs.utexas.edu!utnut!utgpu!pindor
From: pindor@gpu.utcc.utoronto.ca (Andrzej Pindor)
Subject: Re: Grounding Representations: ("Grounding" is the wrong word)
Message-ID: <D7pIGq.Knp@gpu.utcc.utoronto.ca>
Organization: UTCC Public Access
References: <departedD5xB4A.544@netcom.com> <3lkl8d$2gm@percy.cs.bham.ac.uk> <3lkrpq$kun@mp.cs.niu.edu> <3nhlk5$i7o@percy.cs.bham.ac.uk>
Date: Thu, 27 Apr 1995 18:38:50 GMT
Lines: 74
Xref: glinda.oz.cs.cmu.edu comp.ai.philosophy:27297 comp.ai:29357 comp.robotics:20203 comp.cog-eng:3109 sci.cognitive:7437 sci.psychology:40805

In article <3nhlk5$i7o@percy.cs.bham.ac.uk>,
Aaron Sloman <A.Sloman@cs.bham.ac.uk> wrote:
........
>In a thermostat, and perhaps some simple organisms, the link between
>internal information store and and thing representated is very
>direct. In people the causal links are very indirect and the same
>sensors (and motors) are shared between huge numbers of different
>concepts, with many intermediate levels of processing between
>sensory transducers and states like beliefs.
>
>The more indirect (and overloaded) the causal links between
>representations and referents, the more the meaning depends on
>structure not causation. In humans I believe structure dominates,
>and causal links serve merely to reduce ambiguity of reference
>(which can never be completely eliminated).
>
>The structure of our internal information states is so rich, and the
>architecture that uses them is so complex that the bulk of human
>meaning comes from the interaction of structure and manipulation.
>
Experiments with very young kittens, who from birth were brought up in an
environment with vertical lines only and which were found later to be unable 
to see horizontal lines seem to suggest very strongly to me that a large
part of what you call structure and manipulation has its source in causal
links. 
............
>(b) In fact it may turn out easier to design and implement a
>disembodied (or perhaps I should say "disconnected") mathematician
>whose mind is concerned with nothing but problems in number theory
>(and who enjoys the thrill of discovery and experiences the sorrow
>of refutation) than it is to design and implement a robot with
>properly functioning eyes, ears, arms, legs, etc.
>
In case of abstract mathematical terms it may very well be that their
complete meaning is contained in a web of internal links, with no causal links
involved. In fact Harnad, asked whether one can talk about meaning of abstract
mathematical terms in view of his concepts on grounding, ducks the question. 
On the other hand it is not unlikely that when we think about abstract ma-
thematics, we do so by mapping mathematical terms and their relationships onto
mental structures which have come into being by our exposition to sensory
stimuli.

>Of course, if the mathematician really lacks sensors and motors,
>then we shall have no way of finding out which theorems it is
>exploring etc., unless we can use our knowledge of its design and
>direct measurement of internal physical states. But this will be
>analogous to decompiling a machine code program, which can be
>impossibly difficult.
>
>Anyhow the important thing is not to speculate about what is
>possible, but to get on and do it, or find out exactly why it is
>impossible. So let's have a go at designing the mathematicion.
>
Such 'mathematicians' are being designed. A programm Graffiti by Siemion
Fajtlowicz from University of Huston may be a case in point. An interesting
thing is that such programms work differently than a human mathematician
(for instance they have no 'mental structure' derived from sensimotoric
stimuli, suggested above) and hence may work out results (conjectures in case
of Graffiti) which would not occur to a human.


>Aaron
>--
>Aaron Sloman, ( http://www.cs.bham.ac.uk/~axs )
>School of Computer Science, The University of Birmingham, B15 2TT, England
>EMAIL   A.Sloman@cs.bham.ac.uk  OR A.Sloman@bham.ac.uk
>Phone: +44-(0)121-414-4775       Fax:   +44-(0)121-414-4281

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
