Guy Hoelzer  wrote in
news:c76iee$24g$1{at}darwin.ediacara.org: 

 
> Note that I have snipped one sentence out of a longer post.
> 
> in article c71mk7$1kpj$1{at}darwin.ediacara.org, William Morse at
> wdmorse{at}twcny.rr.com wrote on 5/1/04 7:32 PM:
> 
>> Why should the fact that evolution is constrained by physics imply
>> that we should invoke physics as a "primary explanation"?

 
> Good question.  Physical constraints alone do not build an engine of
> work like life.  They are not enough, which is why many folks,
> including myself, are now calling for a re-evaluation of the
> thermodynamic laws (either a modification of the second law, or the
> addition of a fourth law).  We are striving to put the "dynamics" into
> the laws of thermodynamics.  The traditional understanding of the
> second law as a "ONE WAY" traffic sign is only a constraint.  It does
> not make anything go that way. 
> 
> Setting aside the potential for an improved understanding of physical
> dynamics, your question seems to imply that biology is somehow more
> than just its physical underpinnings.  I am curious as to just what it
> is that you think it is about biology that is not physical.  Is there
> biological metaphysics?  If so, isn't the science of biology doomed
> due to the absence of rules that we can know of governing metaphysics?
 
Dang! Now I have to try to remember what I was thinking when I made that 
statment :-)

But before I do that: isn't the science of physics doomed due to the 
absence of rules that we can know of governing metaphysics? Assuming a 
reductionist stance for now - that biology is explained by chemistry, and 
chemistry is explained by physics - then I have to ask the question: what 
explains physics? Is there physical metaphysics? There appear to be three 
possible answers - probably Dr. John (Wilkins) can come up with more: 

(1) the cosmological argument is correct, and there is a prime mover 
somewhere who decreed what the speed of light would be, and what Planck's 
constant would be, etc., etc.;

(2) there is an infinite chain of regression, and we will always find a 
further reductionist reason for the reason (protons are explained by 
quarks, quarks are explained by string theory, string theory is explained 
by something we haven't come up with yet, etc. ad infinitum) I call this 
the turtle theory, after the joke about the world being held up by 
sitting on the back of a turtle - "but what holds up the turtle?" - 
"another turtle" - "but what holds up that turtle?"-
"another turtle" - 
but what holds"- "give it up, kid, it's turtles all the way down"

(3) the ontological argument is correct, and existence implies essence. I 
actually like this argument, at least compared to the alternatives,   
although I disagree with St. Anselm that it proves the existence of a 
Supreme Being. It seems possible to me that  if you have existence, then 
you must have non-existence, so you have a 0 and a 1. Given a 0 and a 1 
you can construct binary mathematics, and from that you can construct 
mathematics in general. Now I have no idea how you get from that to 
Planck's constant, but that's just a minor detail :-)


Having got that off my chest, my statement was really based on my 
interpreting "primary explanation" as more akin to final cause than 
formal cause.The mackerel has a deeply forked tail because fluid dynamics 
dictates that as the best shape for high speed swimming in water if 
maneuverability is less important, but the reason that a mackerel needs 
to swim fast with limited maneuverability is related to selection for its 
niche. 


I do believe that in some cases it is appropriate to invoke physics or 
chemistry as a primary explanation. For instance, I would argue that most 
animals are bilaterally symmetrical because of chemical constraints on 
development, not because of selective bias for that form.  I was mostly 
arguing against taking this to the extreme position of using physics as 
the final cause for all of biology. While this may be true, it is 
probably unprovable and in any case is often of no help in our 
understanding.

Yours,

Bill Morse
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