Francis,
I meant choice in the sense of existing alternatives, not of cognitive
choice.
> 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.
You pointed out that choice is an anthropomorphic notion, notice that so
is selection. You (and Ashby) say that in the transition from one state
to another (including stochastic transition) the system is selecting
states leading into attractor basins, and eliminating the states which
the system does not visit in its trajectory. But really there is no
selection at all in following transition rules, because the states out
of the trajectories leading to attractors were never alternatives to
begin with.
In Darwinian evolution, the term selection (which unfortunately is very
anthropomorphic leading to many confusing evolutionary arguments) means
that those lineages or organisms which are better adapted to their local
environments will have higher rates of reproduction and thus enlarge
their numbers (are selected) in the population of organisms in such
local environment. That is, natural selection is defined as a
statistical
bias on the rate of reproduction of lineages.
This kind of selection is very different from dynamical systems
"selecting" their trajectories. It requires the existence of
reproduction so that rates can increase, which in turn requires coded
construction (genetic reproduction/Von Neuman model). Though all
components of systems participating in evolution based on natural
selection are themselves material and therefore following dynamic
transition and self-organization, such systems possess a kind of
organization that distinguishes them from pure self-organization.
Namely, description-based 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.
Thanks. This is fine with me, but I prefer to restrict selection to
external selection (which requires reproduction, etc.).
I am aware that Ashby defined self-organization as an interaction
between 2 systems. Indeed, the notion of selected self-organization is
probably very inspired by his thought (also on "The Self-Reproducing
System), however, when Ashby wrote those papers (1962) he was trying to
define what could possibly be named a self-organizing system. Today,
this
definition has been more precisely understood. In particular, I abide by
the definition I sent in my previous post, basically that of dynamical
systems reaching basins of attraction.
However, the notion of adaptation in the following Ashby's quote is very
incomplete:
>
> "every isolated, determinant dynamic system obeying unchanging laws will
> develop
> organisms that are adapted to their environments."
>
>
I am not sure which kind of adaptation he had in mind, but dynamic
determinacy is clearly not enough a requirement for open-ended
evolution. As I often discuss in this list, we need description based
reproduction.
Cheers,
Luis
______________________________________________________
Luis Mateus Rocha
Complex Systems Modeling Team
Computer Research and Applications Group (CIC-3)
Los Alamos National Laboratory, MS B265
Los Alamos, NM 87545, USA
T: 505-665-5328
e-mail: rocha@lanl.gov or rocha@santafe.edu
www: http://www.c3.lanl.gov/~rocha