Choice is an anthropomorphic notion, which I would not apply to describe
either Darwinian evolution of self-organization. This leaves us with the
notion of determinism to distinguish self-organizing from selected systems.
As usual, I consider determinism to be a red herring. Determinism is a
purely metaphysical concept, with no operational value. We can never prove
that something is either determined or not. At best, we can ascertain its
degree of predictability. But nothing can ever be predicted with 100%
certainty, so predictability is at best a relative notion, depending on how
much information you have about the process.
Pure determinists (like, I suspect, Mario Vaneechoutte) would argue that
Darwinian evolution too is a deterministic process: it is simpy too complex
for us to gather enough information so that we could predict that one
variation will appear or be selected rather than another, and therefore it
SEEMS indeterministic. On the other hand, most real self-organizing
processes (in contrast to formal models such as cellular automata or
Boolean networks) are clearly unpredictable. Therefore, typical
self-organizing phenomena like phase transitions, emergence of Benard
rolls, dissipative chemical reactions, etc., are modelled by stochastic
processes, where we can at best determine the *probability* of a certain
fluctuation pushing the system into one attractor rather than another one.
If we forget about the red herring of determinism, it becomes clear that
the processes which Luis defines to be self-organizing can be
conceptualized equally well as selection processes. I cannot formulate this
better than Ashby did in the paper Principles of the Self-Organizing System
(1962) that I mentioned earlier (just replace his term "equilibrium" by
"attractor"):
"The argument is simple enough in principle. We start with the fact that
systems in general go to equilibrium. Now most of a system's states are
non-equilibrial. So in going from any state to one of the equilibria, the
system is going from a larger number of states to a smaller. In this way,
it is performing a selection, in the purely objective sense that it rejects
some states, by leaving them, and retains some other state, by sticking to
it. Thus, as every determinate system goes to equilibrium, so does it
select. We have heard ad nauseam the dictum that a machine cannot select;
the truth is just the opposite; every machine, as it goes to equilibrium,
performs the corresponding act of selection."
Note, by the way, that Ashby speaks here about state-determined systems,
although that is not necessary. I prefer to think in terms of Markov
processes, where the next state is not fully determined by the present
state. The result is the same, though: both types of systems have in
general attractors, and the states inside these attractors are selected,
while the states in their basins are eliminated.
>Of course out of families of selforganizing systems one can discuss the
>existance of possible trajectories, or better, attractor landscapes, and
>envision a process of selection of those, which happens in evolutionary
>systems. But this is not a process of self-organization alone, more what
>can be referred to as selected self-organization.
I like your concept of selected self-organization, and I believe it is
important. However, I would just make a slight change in the terminology
and call it "externally selected self-organization". Then it would be a
nice way to conceptualize the interaction between internal and external
selection on a system.
>We can of course change levels of description and try to describe
>evolutionay trajectories in an ecosystem as a self-organizing system,
>but at that point, you are not studying the selection process, namely
>genetic variation and Darwinian evolution, but more general historical
>trajectories. It may be possible in some cases to evaluate evolutionary
>trajectories as a self-organizing system, once historical data is
>available. But in any case, it is a different system which is being
>studied; this does not mean that evolution and self-organization are the
>same thing depending on how you look at it, as much as studying
>biochemistry is not the same as studying evolutionary biology.
I agree that when you look at an ecosystem rather than at an organism in
interaction with its environment, you are considering different systems.
However, you are still looking at the same process. When you consider it
from the point of view of the ecosystem, you see more of it, since you are
aware of the interactions of the different subsystems within the larger
ecosystem. If you only look at the organism, you aggregate all other
subsystems into one "environment" system interacting with your organism.
Therefore, your model will be simpler, but less reliable. But that is your
choice in modelling, not a sudden change in the dynamics of the system.
Ashby too developed this point in his paper, when he noted that you could
conceptually split up any complex self-organizing system into an "organism"
and an "environment". Self-organization (reaching an attractor) then would
look as if your "organism" managed to adapt to its environment. In his
words:
"every isolated, determinant dynamic system obeying unchanging laws will
develop
organisms that are adapted to their environments."
________________________________________________________________________
Dr. Francis Heylighen, Systems Researcher fheyligh@vub.ac.be
CLEA, Free University of Brussels, Pleinlaan 2, B-1050 Brussels, Belgium
Tel +32-2-6442677; Fax +32-2-6440744; http://pespmc1.vub.ac.be/HEYL.html