>What I am concerned with is the concept of what I
>call "multiple views." Don's/Rosen's view of a "complex system" has
>very little to do with how complex it is in terms of the number of parts
>it has and the intricacy of its interactions.
>
>If I understand it correctly, their view is that to understand such a
>system, one needs to view it from at least two points of view. More
>important, these multiple views yield a model of the complex system that
>can not be derived from or understood in terms of the other models of
>the same complex system. So what you have is a definition of a complex
>system that says it is at once the same as and yet differs from itself.
Norm, it looks like you want to distinguish between mechanisms
that allow exhaustive modeling (i.e., any other model is derived from
the the exhaustive model) and organisms that do not allow such an
exhaustive model. I am afraid that there is no such distinction.
Mechanisms can be described exhaustively only if they work well
(i.e., in accordance with the purpose of their creation). But if
they fail, then they are no longer described by this exhaustive model.
For example, a tape player is a perfect mechanism until it starts
jamming the tape. This jamming does not fit to any single model.
There may be infinite models of jamming. If a Turing machine
starts jamming the tape, it is not a mechanism any more. Thus,
mechanism is not just a "simple object" but an object considered
from the point of view of a single function.
My argument seems to agree with Don Mikulecky and Robert Rosen:
"Complexity then ceases to be an intrinsic property of a system,
but it is rather a function of the number of ways in which we
can interact with the system..."
"In a very real sense all natural systems are complex."
I consider Rosen's ideas very valuable, but my impression was
that his understanding of purposes (usages, functions) largely
remained anthropocentric (as in most of cybernetics). I did not found
a place for natural selection in his formalism. Don, please correct
me if I am wrong. Although he mentioned natural selection in a
couple of places, it was not his main interest. Thus, I like more
writings of Pattee and Turchin.
-Alexei
-------------------------------------------------
Alexei Sharov Research Scientist
Dept. of Entomology, Virginia Tech, Blacksburg, VA 24061
Tel. (540) 231-7316; FAX (540) 231-9131; e-mail sharov@vt.edu
Home page: http://www.gypsymoth.ento.vt.edu/~sharov/alexei.html