Path: utzoo!attcan!uunet!bionet!cpswh.cps.msu.edu!sticklen
From: sticklen@CPSWH.CPS.MSU.EDU (Jon Sticklen)
Newsgroups: bionet.molbio.bio-matrix
Subject: re: Peter Karp's Note
Message-ID: <8905231357.AA02176@cpswh.cps.msu.edu>
Date: 23 May 89 13:57:43 GMT
Sender: daemon@NET.BIO.NET
Lines: 48


I agree with Peter Karp's note that it would be useful to
have a clarification of the goals of the biomatrix project.
I suppose Peter and I, as both CS folks who are following
the biomatrix work with interest, would be helped to know
how we can contribute by knowing better what you all want.

To address Peter's comment, it would seem that there
are some real differences between deep and shallow
expert systems, but to pursue that here in detail would not
too productive - its an argument mostly rooted in technical
AI issues. I will look for Peter's paper with interest.

But there is one facet of Peter's note that I think is important
for discussion here. Peter raised the issue of "surface level"
understanding being an approximation to "deep level" understanding
that is sometimes practically speaking the only way we can
go; as in - we have to model the celestial mechanics of the
solar system by approximation techniques even though we know
that an exact solution is theoretically possible.

The general model that Peter is relying on here is one in which
one can think of layers of description of some phenomena with the
lowest level being the "first principles" level and each successively
higher level being implemented on the next lower one: ie, a reductionist
model of understanding.

A difficulty may arise when we try to apply this model to biological
phenomena as follows. When we try to reduce one level of understanding
to another, we loose the descriptive power that the terms at the higher
level afforded, and are forced to use the vocabulary at the lower level.
Eg, mating behavior of large mammals may be reduced through a number
of steps (in principle perhaps) to the bio-molecular level and beyond.
But if we do that, then we cannot use terms like "drive to find a mate"
because such terms do not exist at the bio-molecular level. One of the
most pressing needs when trying to represent a phenomena is to search
for the appropriate level of description to capture understanding.

Going further, one of the most pressing needs of the bio-matrix project
(it seems to me) is to find a representation scheme that is robust 
enough to support descriptions of different phenomena at many different
level of abstraction, and that allows each description to utilize 
terms appropriate to the phenomena being described.

	Jon Sticklen
	AI/KBS Group - CPS Dept
	Michigan State University
	East Lansing