>BH>Stephen, this is an amazing statement. I would be interested in
>>seeing a definition of "evolutionary theory" which excludes
>>Kauffman's theories.
>
>I am no expert on Kauffman's theories, but I assume that mainstream
>Neo-Darwinism would allow at best only a marginal role in its
>blind wathmaker "evolutionary theory".
>
My main point was that "evolutionary theory" =/ "neo-Darwinism".
For example, to the extent that PC is a theory, it is an
evolutionary theory ;-).
In view of Daniel Dennett's trashing of Stephen Gould that I
mentioned previously (in <Darwin's Dangerous Idea>) I was
more than a little surprised to see him treat Kauffman rather
kindly. Dennett has a section devoted to Kauffman entitled
"Stuart Kauffman as Meta-Engineer" in which he tries to bring
Kauffman back under the umbrella of orthodoxy, so to speak :).
It will be interesting to see if Kauffman responds to this.
I have read quite a bit of Kauffman and feel that Dennett has
distorted his position quite a bit, in particular I think that
it is precisely people like Dennett that Kauffman is rebelling
against. Dennett seems to be sensitive about this, even mentioning
that some "... will be strongly motivated to suspect that I am
merely reworking Kauffman's ideas to fit my own biased view!"
Indeed, I am suspicious ;-).
This follows a quote of Kauffman, part of which reads:
"Natural selection, whatever our doubt in detailed cases,
is surely a preeminant force in evolution."
-- Kauffman as quoted by Dennett
Dennett goes on to say:
But, then, what can be his point about "spontaneous self-
organization" as a source of "order" if not a flat denial
that selection is the ultimate source of order?
-- Dennett
Dennett goes on to try to answer this question, all I want to
point out here is the subtle switch from Kauffman's "...*a*
preeminant force in evolution" to Dennett's "... *the* ultimate
source of order". [emphasis mine]. Unless I have sadly
misunderstood Kauffman, there is simply no way that he views
selection as the ultimate source of order.
Now, if we go to the source from which Dennett quoted we
find, just a few paragraphs later:
We shall in fact find critical limits to the power of
selection: As the entities under selection become
progressively more complex, selection becomes less
able to avoid the typical features of those systems.
Consequently, should such systems exhibit spontaneous
order, that order can shine through not because of
selection but despite it. Some of the order in
organisms may reflect not selection's success but
its failure.
-- Kauffman <Origins of Order>, p. xv
Dennett does not quote this particular passage but he does quote
something similar to it, but considerably less offensive :), i.e.
the quote he gives ends with "The structure of fitness landscapes
inevitably imposes limitations on adaptive search."
He then says that this is "... all pure Darwinism" :) and tries
to tie "limitations" in with orthodox views on historical
contingency and frozen accidents. This despite the fact that
Kauffman is strongly opposed to this type of "explanation".
In fact, a major theme of the "self-organizationalists" is
opposition to historical "explanations" and I don't think
anyone has been more outspoken about this than Brian Goodwin.
In the discussion following a paper he presented at a symposia
he made the following comment:
GOODWIN: Let's pursue the question of explanation. I do not
regard natural selection as an adequate explanation of the
forms we see in nature, because it addresses the question
of persistence. And what we want to understand is _existence_:
Why are these things possible? Unless you have a theory that
tells you why these forms are possible, you're going to go
around forever debating questions like, you say,
"It's an accident. It must have been an accident because
no engineer would have designed the vertebrate retina the
way it is." I would argue that the reason the vertebrate
retina is designed the way it is, is because of the basic
constituents of the morphogenetic process that generate
nervous system, the optic stalk, the bulb, the interaction
with the epidermis, the formation of the optic cup, and so
on. I would argue that is intrinsic to the morphogenetic
sequences that occur there. Let me stress that if you only
look at stability and that's all that natural selection
addresses-you are not explaining possibilities; you're
not explaining why they are possible. You're simply saying
why they persist. That is not, for me, an adequate explanation.
[...]
A little later there was this interesting exchange with Murray
Gell-Mann:
G00DWIN: It's necessary to clarify the language that was
used. I'm a biologist, so I grew up with this stuff. It
took me thirty years to try to work my way through this
swamp of confusion that I find in the conceptual basis
of biology.
Let me give you a tiny example: why does the earth go
around the Sun in an elliptical orbit? It's perfectly
correct to say that it did that because last year it
was in an elliptical orbit, and the year before that,
and the year before and back to the origin of the
planetary system. So, that's a perfectly correct
statement and an historical explanation. The initial
conditions determine the trajectory. I'm in no sense
denying that. That is always part of the dynamical
process, as well. It's always got history built into
it. Because, from the set of the possible, certain
things are realized under certain conditions. Now,
if that is accidental, we say, "That's accidental."
What I want to push for is to reduce the realm of the
accidental to the absolute minimum...
GELL-MANN: Well, to what it is; not necessarily the
absolute minimum, but to what it really is.
GOODWIN: The same statement.
GELL-MANN: It may not be the absolute minimum.
GOODWIN: The minimum that we can achieve is as far as we
can go. That's why I'm polemical about it: because there
are so many historical explanations that are used in
biology that shut off students' minds, and they think,
"That's it; that's an explanation." It's _not_ an
explanation.
GELL-MANN: You're mad at a bunch of people who aren't here.
GOODWIN: You seem to collaborate with them, Murray!
GELL-MANN: All this resentment is misdirected against us!
GOODWIN: Put history back in its proper place; that's the
objective.
[in _Complexity: Metaphors, Models, and Reality_, G. Cowan,
_et al_ eds., Sante Fe Inst. Proc. volume XIX,
Addison-Wesley, 1994, p 216-218.]
Now back to Dennett, I think his real concern shows through in
the following paragraph:
Kauffman wants to stress that the biological world is much
more a world of Newtonian discoveries (such as Turing's)
than Shakespearean creations, and he has certainly found
some excellent demonstrations to back up his claim. But
I fear that his attack on the metaphor of the tinker feeds
the yearning of those who don't appreciate Darwin's
dangerous idea; it gives them a false hope that they are
seeing not the forced hand of the tinker but the divine
hand of God in the workings of nature.
-- Dennett, <Darwin's Dangerous Idea>, p. 227.
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Brian Harper |
Associate Professor | "It is not certain that all is uncertain,
Applied Mechanics | to the glory of skepticism" -- Pascal
Ohio State University |
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