Re: Evolution: Facts, Fallacies, Crisis

Greg Billock (billgr@cco.caltech.edu)
Fri, 12 Dec 1997 09:09:54 -0800 (PST)

Lloyd Eby:

[...]


> What is Evolution?

[...]

Have you read _One Long Argument_ by Mayr? He gives 5 aspects of
evolutionary theory as set forth by Darwin. In my experience, the
biggest confusions in popular usage are between four very different
theories.

First, anti-evolutionists often confuse evolution (the biological
theory) with the Big Bang theory, solar nebular theory, stellar
evolution, and so forth.

Second, there is a popular usage to the word (which formed the
reason why Darwin didn't like it much) meaning some sort of
progressive change, a societal or personal development. This
usage is often projected onto the biological theory as well.

Third, there is the theory of common descent, which is a part
of the body of evolutionary theory, but is often what anti-
evolutionists object to..."I don't believe people came from
monkeys!" This is an assumption for most modern work on the
subject.

Fourth, there is the group of theories about how common descent
(and current evolution) took place--which forces drove it, what
their relative importance is, what limiting factors are there,

> 5. 3 + 4 together (i.e., mutation + natural selection, in
> whatever way these may be understood) are the cause of *some*
> (but not all) changes in biological organisms.

This is the neo-Darwinist position.

> Group-B:
> 6. 3 + 4 together (i.e., mutation + natural selection) can
> account for *all* changes in biological organisms (i.e., can
> account for all speciation and the coming into being of all
> biological differences and biological structures, after the
> first living cell appears).

No evolutionists believe this.

> 7. 3 + 4 together (i.e., mutation + natural selection) are the
> only possible (or intellectually credible) account for all
> changes in biological organisms.

Or this.

> 8. Metaphysical naturalism must be accepted as the only (possible
> or intellectually credible) stance. (As opposed to
> metaphysical supernaturalism or theism.)

Some believe this, however. This is a philosophical argument,
though, not one particularly identified with biological evolution--
why evolutionary theory instead of gravitational theory is
singled out by Johnson and others for objection in this regard
seems a bit mysterious.

> 5 are true. *If evolution is defined as claiming that any or all
> of the statements 1 through 5 are true, but only that,* then we
> can say that evolution is conclusively shown to be true. Thus, if
> the claim "evolution is true" means *only* that one or more of
> the statements 1 through 5 is asserted to be true, then that
> claim "evolution is true" is warranted or true.

> Here, however, is the most important point: The truth of any
> of the statements 1 through 5 -- or of all the statements 1
> through 5 taken together -- does *not* yield the truth of *any*
> of the statements 6 through 8.

However true that may be, it is hard to see how that impacts the
debate, since no evolutionists maintain either 6 or 7, and 8 is
a much broader base which everyone doing science, medicine, business,
interior decorating, plumbing, watch repairing, and political
campaign junketing takes as a working hypothesis.

> The error in much evolutionist thinking and argumentation comes
> about, I think, because of this confusion: 1 through 5 are known
> to be true. Moreover the truth of 1 through 5 offers some
> evidence toward the truth of one or more of the statements 6
> through 8. On that basis, many evolutionists go on to assert that
> one or more of the statements 6 through 8 is true.

I think we'll need more evidence than this that any evolutionists
believe that 6 or 7 is true. There was a time, BTW, when practically
no evolutionists believed Darwin's selection theory accounted for
much of any of biology. The neo-Darwinian group of theories has
placed selection back in a prominent role, but certainly not as
the only operator. Neutralist theory, genetic drift, horizontal
transfer, and (I can hardly believe you're missing this one ;-))
sex are all key components of the modern synthesis. Current
arguments rage over their relative importance, and about how best
to understand the units of selection, and about the details of
the dynamics of the processes.

> I need to consider for my purposes here.) On the basis of the
> truth of 1 through 5, Dawkins then goes on to assert the truth of
> 6 and then 7 *without giving anywhere near sufficient evidence
> for their truth* -- instead he gives a lot of hand-waving and "it
> must have been's" and "we can only suppose's" and so on -- what

To the contrary, Dawkins *does* think mechanisms other than selection
are responsible for evolutionary history, he just doesn't regard them
as interesting. This is a topic of much heated debate on talk.origins;
I suggest you take a look there under 'High Table' 'Dawkins' 'selectionism'
and see what you find.

> scientific investigation. As you can tell from my tone here,
> Dawkins irritates and offends me immensely; I regard *The Blind
> Watchmaker* as being not just factually or logically wrong, but
> evil.

My suggestion is that in combatting evil, you make sure to get
the facts straight yourself, or you'll give the appearance of
a rush to judgment.


> First, what is usually called modern science -- that is the
> empirical science of today that goes back at least to Copernicus
> -- has been successful because it has adopted statement 8 (the
> stance of metaphysical naturalism) as its methodological stance.

Science isn't the only human pursuit that takes naturalism as
a methodology. In fact pretty much every human pursuit takes
naturalism as an assumption. Plumbers assume there is some
naturalistic reason why the pipes are blocked--they don't consult
horoscopes and read your palm, they use Roto-Rooter.

> in naturalistic terms -- i.e., it has held that there must be a
> naturalistic explanation (as opposed to a supernatural one) for
> everything. We have methods for testing naturalistic hypotheses,
> but we do not really have methods for testing extra-naturalistic
> or supernaturalistic ones. Another way of making this point is to

How would you suggest we proceed, then, if we abandon naturalism?
Many scientific projects (even naturalistic ones) proceed on the
basis of 'let's see how far we can get with this line of approach.'
This is usually because it is just too hard to crunch out the
more complete theory, so an approximation is used to try to make
progress. The same is true for whole research programs--they try
to make sense of some mystery given the current theories afloat,
and see how far they get. Solar neutrino research is a good
example. If you are suggesting we incorporate supernaturalism
into our theories, you need to provide at least two methodologies.
First, we need a method to determine when to pull in the
supernatural. Is it after the first attempt fails? "Well, epicycles
just can't explain the bright dots around Jupiter, so the whole
of astonomy must be supernatural, let's go do something else."
Is it when the best, most up-to-date attempt fails? Is it after
40 years of failure? Second, we need methods to adjudicate between
competing supernaturalistic explanations. While judging between
naturalistic theories is seldom as clean as "do the experiment and
see," I'm not sure there is any acceptable precedent for adjudicating
supernaturalistic theories.

> not have come about. Moreover, although there may be ways of
> testing extra-naturalistic hypotheses, we have not, in fact,
> possessed them in any way that we could really call scientific.
> The question of whether extra-naturalistic hypotheses and
> explanations can be tested in any adequate way thus remains open
> and unanswered, I think. Another way of saying this is that we do
> not at this time have available any good or adequate model or
> paradigm for a non-naturalistic science.

That may be, but before castigating people for not using these
undefined methods, it might be more appropriate to first define
them, show how beneficial they are, and then offer them for use.

[paradigm shifts]

Paradigm shifts in science have typically come from a new research
program gaining much more momentum than its competitors, and
simply sweeping them off the field. One key ingredient in this
process (what many scientists wish was the only ingredient) is how
well the research program is doing in solving interesting problems
in a field. You can't build momentum in science on rhetoric alone--
you need a replacement method or theory which does better than
the competitors and, hopefully, explains where and why they were
wrong. The supernaturalistic research program seems to be stalled
in the rhetoric stage--it has produced no interesting and useful
results, no contributions to any area deemed important and interesting
by other scientific programs. When it progresses beyond the pouting
and foot-stamping stage, it will, perhaps, be worth listening to.
(And don't think for a second that naturalistic research programs
don't go through this stage! :-)) It is the responsibility of
folks like yourself to push the program forward.

-Greg