Chris
Actually, that was already held by some, I think.
Darwin's contribution was that evolution proceeds by variation and culling
(what is misleadingly called "natural selection") and by providing a large
amount of detailed (for his time) support for this idea.
Neo-Darwinism goes further, links this evolutionary process to genes, posits
additional mechanisms for variation, and so on. But the only real
requirement is that it be an *empirical* theory, that it not posit any
metaphysically external forces (even a *designer* does not necessarily have
to be an outside force in this sense; it might merely be an alien researcher
using the Earth as a several-billion-year experiment), that it be
empirically *testable* (even if only with great difficulty and considerable
uncertainty), etc.
That's why so many of us do not like the "it looks designed to *me*"
argument that so many ID theorists use. That's not really an *argument*, so
much as an assertion of how one's own mind has *interpreted* what it sees.
To *make* it an argument, the details and basis of that interpretive process
have to be brought out into the open where they can be examined. ID
theorists seem to have great trouble doing this, because, whenever they make
the attempt, what comes out turns out to be little more than that Nature is
orderly and that living organisms function in a pseudo-purposeful way (those
that don't, don't survive, of course, so that's to be expected on purely
naturalistic grounds as well).
Of course, much of neo-Darwinism might be salvaged even if some sort of
designer did turn out to exist, particularly if the designer only intervened
*initially* to set up the mechanism and give it a "push" (by providing a
planet and Sunlight, etc.).
We neo-Darwinists would like to claim abiogenesis, but that was a historical
event, so all we can do is show that it was apparently possible, by showing
that there is no *major* difference between the *simplest* living organism
and many equally-complex and nearly-identical *non-*living organisms (take
the simplest organism, and move one atom to a new location so that the
result is now a non-living organism). Since we can already demonstrate that
some molecules can reproduce and evolve, it is clearly not a big thing to
suppose that some such molecules eventually evolved into living things, by
gradually accreting the functions of living things over a period of many
generations, until, finally, one such collaboration of atoms became a truly
living thing (able to absorb other molecules into itself and use them for
the furtherance of its own existence, perhaps).
Also, finally, I'm not at all sure that neo-Darwinists would require that
Nature be *basically* devoid of purpose, but only that the origin of life
and its development be not *directly* driven by purpose. That is, it may be,
for example, that the Solar system (or the whole Universe) was set up by a
designer in order to produce just exactly the results that *have* been
produced. This would be purposeful, but not a reflection on neo-Darwinism,
which only deals with the evolution of life *given* our Universe, not with
how or why the Universe was exactly the way it was before life originated.
As a naturalist, I would reject such a theory, but, as a neo-Darwinist, it
is simply *irrelevant*, because, no matter *how* the pre-life situation came
about, there is no reason to believe that design was directly involved *at*
the time of the origin of life or during its evolution to the present.
Neo-Darwinism does not reject ultimate purpose, but merely has no use for
it.