Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!orion.oac.uci.edu!jhess
From: jhess@orion.oac.uci.edu (James Hess)
Newsgroups: comp.ai.philosophy
Subject: Re: Emergent properties (was: What AI is exactly)
Message-ID: <2711520B.6825@orion.oac.uci.edu>
Date: 9 Oct 90 04:28:59 GMT
References: <15132@venera.isi.edu> <84118@tut.cis.ohio-state.edu> <1990Sep27.185805.21493@ncsuvx.ncsu.edu> <8629@helios.TAMU.EDU>
Reply-To: jhess@orion.oac.uci.edu (James Hess)
Organization: University of California, Irvine
Lines: 62

In article <8629@helios.TAMU.EDU> n025fc@tamuts.tamu.edu (Kevin Weller) writes:
>In article <1990Sep27.185805.21493@ncsuvx.ncsu.edu> fostel@eos.ncsu.edu (Gary Fostel) writes:

>>  A second example: if you put large pine forrests, rabbits and foxes
>>  together in northern Canada, you will get a 10 year cycle of boom
>>  and bust in the populations of rabbits, foxes and young pine trees.
>>  (Rabbits LOVE to eat pine needles, far more than carrots.)  Is this
>>  pattern an emergent property?  From the perspective of a naive and
>>  innumerate individual, the answer is certainly yes.  The cycle is
>>  there, it was not predicable (by them) and it is not easy to 
>>  identify the source in myopic analysis of rabbits, foxes, or pines.
>>  From the perspective of an ecologist or someone versed in simple
>>  dynamical systems theory, it is not an emergent property.  It can
>>  be predicted, modeled, and well explained, based on properties of
>>  the constituent elements, e.g. kilocalories needed, supplied, 
>>  gestation period, etc.
>>
>>  Again, I would expect advocates of the "emergent property" term to
>>  be somewhat bothered by this situation...
>
>On the contrary, I am not bothered by it at all.  Your example is
>simply not one of emergence.  I don't claim that ALL such phenomena
>are emergent.
>
>What I am trying to say is that SOME phenomena CAN NOT be explained
>SOLELY on the basis of component properties.  

I don't quite agree with Kevin in this instance.  An emergent property is
one that emerges from the component properties AND their arrangement into a
system where their INTERACTIONS give rise to properties that are not 
inherent in the component properties alone.  The ten-year cycle above is 
emergent in the system; it would not occur if one of the components was 
removed.

In a sense, the discussion of emergent properties is nothing new.  It becomes
more salient in contemporary analysis as we look at systems that are more 
complex, have more interactions, and the interactions play a more important
part in the behavior of interest.  In particular, philosphers discussing the 
mind/brain problem have often had difficulty understanding how consciousness,
cognition, or intelligence could arise.  It either had to be inherent in a 
component, or be the immaterial gift of God--a mind acting on the brain.

Incidentally, my favorite example of an emergent property was given by Marvin
Minsky in "Society of Mind".  The function or purpose of a box is generally
to contain something--yet any side alone or any subset of its sides have no
property of containment.
>
>>  are unable to explain the observations based on properties deduced
>>  from these atoms, they reach for terms such as "emergent properties"
>>  rather than doing good science and looking to reformulate the basic
>>  hypothosis in new ways.  Hiding behind a pseudo-science of "emergent
>>  properties" will probably delay the real struggle: to find more
>>  suitable analytic tacts and more suitable atoms to form the 
>>  foundation of a "proper" scientific explanation.
>>
It seems from Gary's discussion that he thinks emergence refers to some kind
of unanticipated, undeducible property that scientists use when analysis fails.
Instead, it is precisely the more suitable analytic tactic he calls for.

He might then ask, was is not possessed of emergent properties?  I suggest he 
eat sugar-coated cornflakes for breakfast tomorrow and ask himself if they are
possessed of any properties not wholey a property of its parts.