IUBio Biosequences .. Software .. Molbio soft .. Network News .. FTP

Theories of Evolution

Mr V. Schoenfeld DOM vs10005 at crc.ac.uk
Wed Aug 31 06:48:02 EST 1994

In article <9408292013.AA11291 at bambi.ccs.fau.edu>, tomh at BAMBI.CCS.FAU.EDU (Tom Holroyd) writes:
> >And by the way, a clock is not just a lot of pieces. It gives you the time.
> Now you've done it.  Oh well, why not?
> First, just so you all know where I'm coming from and so you won't label me
> a vitalist or something :-), I'm a Ph.D. student at the Center for Complex
> Systems and Brain Sciences here at FAU.  To save time, don't read the stuff
> in [].
> 	[You could argue that the function of a clock is to wobble the
> 	escapement back and forth to create the ticking sound.  But I won't.
> 	:-)]
> Let's examine the position that a clock is a collection of parts and nothing
> more.  If we take a reductionistict stance, we can (literally) take the
> clock apart, see how all the pieces interact, put it back together, and
> create a perfect theory of clock function.  All *without* reference to
> its supposed function of time telling.  And this would be perfectly
> acceptable to any scientist.
> Many biologists appear to take the same approach with living organisms,
> especially molecular biologists.
> There are those who would say, though, that a living organism is not like
> a clock, that it is more than the sum of its parts.  What is meant by this?
> 	[The history of this line of thought is really old.  I've traced it
> 	back to Plato in the West, and I'm sure it's got roots in the Orient
> 	that go back even further.  The basic idea is that of an "undivided
> 	whole" to borrow the title of David Bohm's last book (q.v.).  Any
> 	attempt to reduce such a whole to a formal model (like the perfect
> 	theory of clock function), necessarily omits part of the whole; for
> 	example it may omit some interaction of a system with the
> 	environment.]
> Formal systems are closed.  Real, natural systems are open.  For a clock,
> it is possible to create a closed formal model of an abstract clock that
> has no interactions with the environment; such a model of a living organism
> is obviously absurd.  See, for example, Robert Rosen's work for more on
> this point of view.
> A clock's gears interact basically in only one way, at one level.  The
> perfect theory of clock function chooses this level of description and
> does everything there.
> Living systems have highly complex interactions, at many levels and time
> scales, with many other components of the environment and of themselves.
> These interactions form a network of dependencies where one part of the
> system depends in a non-linear way with other parts.
> 	[And when I say part I have to also say at what time scale and
> 	level of description I'm speaking on - bones are solid structures
> 	at one level but are constantly in flux on another.]
> Removing any part affects the total system in often unpredictable ways.  It
> is in this sense that living systems can be considered to be wholes.
> The "whole" living system really needs to be the entire planet, the whole
> solar system, etc., for each organism is part of a web of interactions with
> other organisms, and isolating an organism from that web alters it, again
> in often unpredictable ways.
> So reductionism fails to be fully effective on living organisms, despite
> the success with the clock.
> 	[Notice that equating a real physical clock with the formal model
> 	is like saying that there are no 'important' interactions between
> 	what is modeled and what is not.  So the model may or may not be
> 	successful, depending on the real importance of those interactions.]
> So what's an honest reductionistic scientist going to do?  Well, you
> can state your level of description, decide what time scales you are
> interested in, and make a closed, formal model of that little bit.
> Notice that you have to assume some underlying physical system which
> has its own set of rules.  If you are really ambitious, you can even
> try to make a model of the underlying system, at its level of
> description, and show how the first model arises from it.  Statistical
> mechanics is an example of how the macroscopic theory of thermodynamics can
> be derived from the microscopic behavior of the components.  But it
> only works at thermodynamic equilibrium, in a closed system, or at best
> in the linear region near an equilibrium state (see Prigogine).
> 	[All this can be applied, by the way, to the brain.  In particular,
> 	it can be applied to the question of whether the brain is a
> 	computer.  A computer is like a clock, the brain is not.  If this
> 	sends up a red flag for you, send me private email and remember
> 	that I'm not a vitalist.]
> So in summary, let us not forget that molecular evolution is a part of
> this whole, this web of interactions.  The high-level behavior of animals
> influences the course of molecular evolution, and all models live at
> a chosen level of description, like statistical models of the likelyhood
> of transposition/transition.  The probabilities are in flux themselves.
> Tom Holroyd
> Center for Complex Systems and Brain Sciences              The basis of
> Florida Atlantic University, Boca Raton, FL 33431 USA      stability is
> tomh at bambi.ccs.fau.edu                                     instability.

Easy boy!
My intention was never to ignite the strong AI argument, I just
found it offensive that someone called futile the wonderful work
done by thousands of molecular biologists. 
Fair enough, a lot of us might not be interested (or pretentious enough)
to put everything they're doing in a  high philosophical dimension.
But let's be honest, before you can start speculating on whether brain
algorythms only are enough to support 'intelligence' or not, it
is necessary  to fully understand how it all works at the molecular level,
perhaps simply to give a model on which to build potential AI computers and by doing
so giving  a chance to the strong AI people to test their models.
And anyway, do we all have to try and find the 'Ultimate answer' or do you mind us
lot carrying on working in order to save lives and relief suffering?

Honestly, I think there are different times for different things. It's all
very nice to see all the theoretical phycisists, brain/computer scientists, etc...
to throw abstract examples at each other's faces in order to find out
who's most clever, but the ground work has to be done. And when one looks at it 
it is actually quite beautiful to observe what evolution has come up with in
terms of an organism's  ability to control its environment or to react to its

I understand your arguments in trying to prove that computers will never have
this 'extra feature' that human brains have (despite being a thick biologist),
but I always find it frustating that people like you always seem to
avoid to name what you think makes us special. Primrose is is an expert at this sort
of game, which is a shame I think. God? Soul? Anything else? Just say it, or
evangelists will always fill the gap for you.

A happy atheist biologist

More information about the Mol-evol mailing list

Send comments to us at biosci-help [At] net.bio.net