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Re: The value of Rosennean Complexity, applied...

Judith, I'll respond more when I have more time. Meanwhile, just to let
you know, I don't in any way think he was saying modeling is pointless,
or that others necessarily take it that way. I think  that in many
minds, since a modeler ends up in the same business regardless of
philosophy, they don't much care if models are incomplete theoretically,
because they know they are already incomplete practically, and nobody
knows what the right way to model is aside from its results. When
modelers come to work they still try to make a better model, so what
does Rosen theory change except their philosophy or design, which people
tend to be very personally attached to, all ideas seeming equal at that
stage. Now I personally know many ways it helps and I'm using them. But
if I give a presentation and say my particular approach to modeling is
based on Rosen's ideas, everybody has to agree to a philosophy in order
to like my model. If I show them how it produces a better result they
are instantly in agreement. Most of the time I can't do that, because
the means of evaluating and comparing models is not well established
either. Most of them are accepted on faith, so again it boils down to
whethr or not you believe the philosophy.. I've been pushing for a
comparison of species models for several years now, and may get some
funds for it this year. Meanwhile nobody knows if Biomapper is right or
Species Analyst is right, or someone's agent-based model is right - all
anyone can do is look at the results. If nobody can tell that you have a
dumb model, who cares about improving it, even if they agree with the
theoretical improvements? Now, one way it has come back at us is with
regard to endangered species and threatened ecosystems. When population
models don't provide the necessary information to prevent a species
crash and listing of, say Pacific salmon, on the endangered species
list, we know the model was too simple. Then everyone comes out of the
woodwork claiming they have a better model, based on many different
philosophies. Those closes to the comfortable and predictable domain of
physics tend to win the faith battles. The problem, as I see it, is that
we don't understand the design principles, as I believe RR did.

J Kineman

Judith Rosen wrote:

Hi Folks,

I was having a discussion via email with someone on the subject of--
What do you do when Rosennean Complexity is saying that complex
systems are non-computable, that all models of them are going to be
incomplete, and yet your job is to make models of complex systems?

Apparently, some of the hostility to my father's theoretical work is
due to a perception that he was saying it's a waste of time to even
try to model these systems. But he didn't feel that way, AT ALL. Quite
the contrary! If I can lay that misconception to rest, I will be very
happy.

Not only did Robert Rosen believe that modeling is useful, he made
extensive use of it himself. He believed it is the only way to deal
with many, many different aspects of science and industry. His
contention was that we need to know how the accuracy of models is
affected by the truth (i.e.; Complexity) and ameliorate the
disconnect-- in as many ways as we can invent, but he suggested
several ways in his books and papers. The upshot of this change in
approach, he believed, will be better models and better results.

In other words, he was attempting to prove that reductionism won't
teach us what life is in the scientific sense, but that doesn't mean a
reductionist approach is bad. It's only bad if one presumes that it's
the ONLY approach and that everything that is outside the bounds of
what you can do reductionistically is unimportant. That's all he was
saying. How many subscribers on the list have been under the
misapprehension that my father was suggesting that modeling a complex
system is pointless? (I sure hope it wasn't very many-- My God! If the
hostility to my father's work is based on this....)

What he was trying to point out is that Complex systems pose certain
built in difficulties when it comes to modeling. He explained why and
described the kinds of "deformities" or inaccuracies that ensue in the
modeled version compared to the real system. His belief was that if
you take these characteristics (of complex systems) into account when
building your model, you can adjust for some or most; you can do
things within the modeling process itself to make your model work far
more accurately than one that presupposes a false premise of
simplicity (which is what all reductionism has at its core).

There are some areas of science that will not be able to use a
reductionist approach very much, if at all, and studying complexity
itself is one of those. Studying the organization of complex systems
(as opposed to the material parts) will require some new thinking.
Otherwise, the only change in applied science that my father was
advocating is a change in mindset, with creativity applied to the
problem that lots of people in science are completely unaware they
have. His work was in the foundations of science, albeit he never set
out to do that. His intention was to be a biologist, only. It was as
he realized that the tools in the tool box were inadequate for some
unknown reason that he set out to reimagine the foundations of science
through history.

Judith 


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© 2004 John J. Kineman
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