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From: minsky@media-lab.MEDIA.MIT.EDU (Marvin Minsky)
Newsgroups: comp.ai.philosophy
Subject: Re: emergent properties
Message-ID: <3919@media-lab.MEDIA.MIT.EDU>
Date: 5 Nov 90 22:23:12 GMT
References: <1990Sep29.213139.2876@watdragon.waterloo.edu> <3499@media-lab.MEDIA.MIT.EDU> <1990Oct26.220658.11281@ncsuvx.ncsu.edu> <3841@media-lab.MEDIA.MIT.EDU> <1990Oct30.220248.20784@ncsuvx.ncsu.edu> <4112@se-sd.SanDiego.NCR.COM> <1990Nov1.205907.7472@ncsuvx.ncsu.
Reply-To: minsky@media-lab.media.mit.edu (Marvin Minsky)
Organization: MIT Media Lab, Cambridge MA
Lines: 33

In article <1990Nov1.205907.7472@ncsuvx.ncsu.edu> fostel@eos.ncsu.edu (Gary Fostel) writes:

>>>The trouble with this dismissal of the "emergence" of gravity is that 
>>>the dismissal is predicated upon a theory that has never been demonstrated.
>I don't think it matters that much whether we are dealling with one particle
>or two.  It could be scads of particles.  No one has ever observed gravity
>acting on anything less than jillions of particles.  We all beleive it acts
>on each particle but that is unfounded.  I don't think there is even any
>indirect evidence of gravity until you get to macroscopic sized objects.
>The gravitional force is many orders of magnitude weaker than even the
>weakest of the other forces.  I don't often find myself disagreeing with
>Minsky, but this time I think he's wrong.  

Wrong about what?  You're right, so far as I know, that gravity has
not been directly measured for pairs of small particles.  But we were
speaking about "emergence".  Because all known experiments confirm
superposition for gravity, we can "explain" all such experiments in
terms of pair-interactions.  So there is no need to postulate that new
phenomena emerge in large ensembles.

Perhaps this discussion is confused because some discussants, like me,
have used the word "emergent" for phenomena that (1)  emerge from large
ensembles but  cannot (or, rather, have not) (2) been explained in
terms of rules for combining the effects observed in small emsembles.
This is different from explaining things in general, such as the
electric force between two charged particles.  This cannot (or,
rather, has not, except, perhaps, by Dirac) be explained in terms of
phenomena observed by single particles.  But for this sort of thing,
we use the term "interaction" rather than emergent.  It isn't a matter
of "right" or "wrong"", but of how we agree to use those words.

I think Gene Roddenberry once quoted Leonard Nimoy as saying, "I
have my faults, but being wrong is not among them".