Boudry and Plantinga argue about the bit that God did
or didn’t do.
My favourite atheist, Larry Moran, has once again alerted
me to some very interesting material that warrants a blog post. In a post entitled
Boundry vs. Plantinga and dated
September 20th Larry gives us news of a review by Maarten Boudry of
Alvin Plantinga’s book Where the Conflict
Really Lies. This review can be found in the IHPST newsletter here. (Just search for “Boudry”).
Needless to say atheist Boudry pretty much rubbishes Plantinga who is Christian. For myself,
however, I find I am unable to support either side of this debate because both
parties seem to be deploying some very dubious concepts and arguments. To be
fair I haven’t read Plantinga and I am only going on Boudry’s representations,
so it could be all Boudry’s fault. Below I have reproduced the section of the
review I’m going to consider here:
In Part I,
Plantinga argues that theism is not in conflict with evolutionary science, only
with unguided evolution, which is a metaphysical add-on, not a part of evolutionary
theory proper. But what about the thesis that the source of mutations is
random, an assumption that is part and parcel of evolutionary theory? “Random”
in this context does not mean pure chance, but rather without foresight, or not
necessarily concordant with the organism’s adaptive needs. According to Plantinga,
random mutation is compatible with God orchestrating the whole process. It is
just God’s way of creating novelty. But there is no wedge to drive between “random”
and “unguided”. If God is steering evolution in the right direction, making
sure that suitable mutations arise, the mutations cannot be “random” in the
technical sense, for then they would occur for the benefit of the organism (or
whichever plan is on God’s mind). This becomes clear when Plantinga, strangely
enough, endorses creationist Michael Behe’s argument from “irreducible complexity”
(IC, see further), a pseudoscientific concept that has been completely rejected
by the biological community. Behe’s argument is that the evolution of IC
systems requires the simultaneous occurrence of different beneficial mutations,
which is exceedingly unlikely. Therefore, some intelligent designer must have monitored
the development of IC systems, if not by miraculous creation, then at least by
causing the requisite mutations for natural selection to work on. But then,
obviously, the mutations arise to meet the organism’s adaptive needs, and are
no longer “random”. That is exactly the point of Behe’s argument. Besides, why
doesn’t God skip the cruel selection part and create a whole population of well-adapted
organisms without further ado? (See below for Plantinga’s answer to the problem
of evil.)
The thesis that
mutations are random (i.e., unguided), rather than being a metaphysical
afterthought, has been amply demonstrated and is accepted as the null hypothesis
by evolutionary biologists. Experiment after experiment has shown that there is
no evidence of nonrandom mutations arising because an organism “needs” them.
Further, if some intelligent agent is triggering mutations after all, it seems
that he/she/it is causing precisely the kind and rate of mutations that one
would expect if the process were entirely undirected. Plantinga’s effort to
stave off the conflict between theism and evolution is a failure. Either he is
buying into creationist fantasies that have been put to rest long ago, or he is
hammering on the excessively weak claim that it is logically and metaphysically
possible that, all evidence to the contrary, evolution unfolds under
supernatural guidance. But if the bar for rational belief is lowered to mere
logical possibility, and the demand for positive evidence dropped, then no
holds are barred. Evolution (or gravity, plate tectonics, lightning, for that
matter) could as well be directed by space aliens, Zeus or the flying spaghetti
monster. (I was going to include the
devil in the list, but then it turns out that, on page 59, Plantinga has no
qualms at all about treating the horned one as a serious explanation. There
goes my reductio.)
In the above I see no cognizance of the single most
important factor which makes or breaks standard evolutionary theory*, namely
the critical importance of the physical regime in making the evolution of
organic configurations possible. It is this regime which determines the size
and shape of the space of permissible configurations in which random
thermodynamic shufflings are taking place. If this space is wrongly shaped or
too large then the thermodynamic agitations which effectively constitute the computational
activity which “seeks out” stable organic configurations, is easily overwhelmed.
But if our physical regime actually returns a sufficiently constrained shape
and size to configuration space then the evolution of organic forms may have a
realistic probability.
If for the sake of argument we assume that the latter
is the case then no further “guidance” (whatever that means) is needed for
evolution; there is then sufficient mathematical providence for evolution to
proceed. For if the configuration space set up by our physical regime is sufficiently
constricted then the random thermodynamic shufflings become the computational
searching by which the configurations of life are located and locked into place
by the evolutionary ratchet.
The “shuffling” patterns of randomness (constituting the natural engine of computation)
are no more and no less than that; namely, a particular class of mathematical
patterning. How then are we to distinguish between patterns that are guided (Plantinga)
and patterns that are unguided (Boudry)? What criterion do we use to
distinguish between guided and unguided patterns? To me the dispute between
Boudry and Plantinga about the nature of evolution seems to be Unintelligible.
Unless, of course, it is claimed that our physical regime is insufficiently
constrained to impose the right shape and size on configuration space – in
which case the evolution of life would require something extra – perhaps some
unknown physics or even the enigmatic “tinkerings” of a homunculus intelligence working behind
the scenes, not unlike Maxwell’s demon! If so then Boudry and Plantinga
would have a meaningful dispute. Otherwise I see little content in their argument.
However, if the mechanisms of evolution (and OOL) are as
the evolutionists think they are then I agree with Boudry that the random
shufflings of the computational engine are going to be statistically
independent of an organism’s need to survive: Unlike Maxwell’s demon those shufflings don’t have any information about the direction in which they should take; in
fact that’s precisely why a search needs to be conducted! But I disagree with
Boudry when he says that Irreducible Complexity is a pseudoscientific concept.
You see, if Boudry accepts the established view of evolutionary mechanisms then
he is implicitly accepting that configuration space has been arranged with the
right shape and size needed to confer upon those mechanisms a realistic
probability of generating organic forms. This shape requires stable organic structures to be close enough together in configuration space to form a linked set so that
evolutionary drift can proceed in a series of incremental steps; where each step is a small jump to the next relatively stable organic form. This condition whereby organic structures form a linked set in configuration space is what may
be termed “Reducible Complexity”. But in positing this concept we beg the
question of whether or not it is in fact the case: What if organic configurations
do not form this connected set? What if organic forms are isolated islands of
stability in a huge sea of unstable configurations? Irreducible Complexity as a
concept is simply the negation of reducible complexity and as such it is both a
meaningful idea and the subject of legitimate scientific inquiry. Should irreducible
complexity actually be the case then needless to say the established view of evolutionary
mechanisms would simply not work and the posited engine of natural history
would have to be fundamentally revised. Perhaps this may explain why Boudry
shrugs off IC in an offhand way, rather than face the uncharted intellectual
vista it brings into view. He is using the word “pseudoscience” as the establishment once used the cry of “heresy”.
If engines of evolution and OOL are as the scientific establishment would very likely prefer them, then this entails the supply of some very particular mathematical
conditions: These conditions must be constantly maintained as the status quo of our physical constitution and therefore
these conditions are arguably an ongoing form of guidance, although guidance that is rather different from
the default “interventional” theology that envisages some kind of homunculus or "demon"; a model that is affirmed by many theists and vehemently attacked by
atheists like Boudry.
Boudry’s review naturally runs into other issues like
the logical possibility of miracles, the problem of suffering and the
destructive self-referencing of naturalism. I may look at these in a later post.
Footnote
*In this context I’m bundling organic evolution and OOL
into one package and calling it “evolution”.
.
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