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Hi Folks,
I've been swamped with work, but as I've been working, I've
also reread some areas of my father's work that I think are worth bringing
into discussion, particularly as they bear on the "Rosennean Modeling Project".
In the General Introduction to "Anticipatory Systems", right after a short
discussion of modeling and side effects, he begins a new
discussion:
"The theoretical principle underlying this analysis of
failure in anticipatory control systems is not wholly negative. In fact, we
shall argue later that it also underlies the phenomena of emergence which
characterize evolutionary and developmental processes in biology. It may be
helpful to cite one more excerpt of a paper originally prepared for the Center
Dialog, [Robert Hutchins' "Center For the Study of Democratic
Institutions"]. which dealt with this aspect:
"It may perhaps be worth noting at this point that the above phenomenon
is responsible for many of the evolutionary properties exhibited by organisms,
and many of the developmental characteristics of social organizations. Consider,
for example, the problems involved in understanding, e.g. the evolution of a
sensory mechanism such as an eye. The eye is a complicated physiological
mechanism which conveys no advantage until it actually sees, and it cannot see
until it is complicated. It is hard to imagine how one could even get started
towards evolving such a structure, however valuable the end-result may be,
and this was one of the major kinds of objections raised by Darwinian evolution.
The response to this objection is essentially as follows: the proto-eye in its
early stages was in fact not involved in the function of seeing, but rather was
primarily involved in carrying out some other functional activity, and it was on
this other activity that selection could act. If we now suppose that this other
activity involved photosensitivity in an initially accidental way (simply
because the physical structure of the proto-eye happened to also be
photosensitive), it is easy to imagine how selection pressure could successively
improve the proto-eye, with its accidental sensory capacity, until actual seeing
could begin, and so that selection could begin to act on the eye directly as an
eye. When that happened, the original function of the eye was lost or absorbed
into other structures, leaving the eye free to evolve exclusively as a sensory
organ.
"This "Principle of Function Change" is manifested even more clearly by
evolution of the lung as an organ or respiration. Many fish possess swim
bladders, a bag of tissue filled with air, as an organ of equilibration. Being a
bag of tissue, the swim bladder is vascularized (possesses blood vessels). When
air and small blood vessels are in contact, there will necessarily be gas
exchange between the blood and the air, and so a respiratory function is
incipient in this structure, designed initially for equilibration. It is easy to
imagine how successive increases in vascularization of this organ, especially in
arid times, could be an advantage, and thus how selection could come to act on
this structure as a lung. This Principle of Function Change is thus one of the
cornerstones of evolution (and indeed of any kind of adaptive behavior), and it
depends essentially on the fact that the same structure is capable of
simultaneously manifesting a variety of functions."
Thus the basic problem of avoiding infinite regresses in anticipatory
control systems could be reformulated as follows: Can we design systems which
are proof against a principle of function change?
This was the circle of ideas which I was led to place on the table at
the Center. The response elicited thereby could perhaps best be described as
restrained, but encouraging. I received some comments to the effect that my
approach was logical and mathematical, and hence fundamentally inapplicable to
politics. In particular, there seemed to be no room for perversity, a major
factor in human behavior. Indeed, I had often noted that almost the only way for
man to prove that he is truly free is to deliberately do himself an injury; to
deliberately act against his obvious best interests. But I did not feel that
this sort of objection was insuperable. Mr. Hutchins himself made few
direct comments, except at one point to remark that one of my conclusions
was the most outrageous thing he had ever heard. I took this as a high
compliment.
--snip--
"For my own part, I continue to believe that the properties of
Anticipatory Systems raise new questions for the scientific enterprise of the
most basic and fundamental kind. These questions have led me to reformulate and
refocus all my previous work in the foundations of theoretical biology, and in
the relation of biology to the physical and human sciences. Indeed, there is no
aspect of science which can be untouched by so fundamental an activity as a
reconsideration of the reactive paradigm itself. The results of this
reconsideration, and its implications, are the basic subject -matter of
the developments which follow.
Now that we have reviewed the genesis of the theoretical problems with
which the present volume [Anticipatory Systems] is concerned, we may turn to a
consideration of the problems themselves. The first and most basic of them is
simply this: What is a model? What is the nature of the relation between two
systems which allows us to assert that one of them is a model for the other? The
basic property of the modeling relation is that we can learn something about a
system in which we are interested by studying a model of that system.
"
--snip--
I think the discussion on the subject of models and side effects is
also useful, so I will post that in the next couple days.
Cheers,
Judith
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