Tuesday, March 16, 2004

HowlersThe latest ID book, The Design Revolution by William Dembski, showed up on my doorstep today. Dembski is currently the only one of the current crop of ID theorists who claims to be doing serious scientific work. All of the other ID output recently has been about pointing out alledged flaws in evolution, or in arguing why their half-baked creationist ideas should be taught in science classes. It is Dembski who claims that by using nothing more formidable than some elementary probability theory, he can positively identify certain biological structures that had to have been the product of intelligent design.

It is for these reasons that I am somewhat encouraged by his current book. It is written in question and answer format, you see, and put out by the Christian publisher InterVarsity Press. Needless to say, this is not how scientific theories are usually promoted. For example, when Stephen Jay Gould and Niles Eldredge came in for serious criticism regarding their theory of punctuated equilibirum, they did not respond by publishing a cheesy collection of questions and answers for nonbiologists. Instead they, along with numerous other like-minded paleontologists, went into their laboratories and came out with actual results. That is what gets scientists to raise their eyebrows.

Dembski's past books have been so technical and have availed themselves of so much jargon that he created an effective illusion that his work actually had some content. Alas, as was obvious to any mathematicaly inclined reader, he was only using the form, and not the substance of mathematics. The present book, however, is so obviously propaganda that there is little danger that anyone not already in the ID camp will be taken in by it.

It didn't take long to find some true howlers:

As my colleague Robert Koons points out, in attempting to account for the emergence of biological complexity, all evolutionists have done is describe supposedly possible mechanisms, in highly abstract and schematic terms, to which, in the case of Darwinism, no significant details have been added since the time of Darwin (and one can argue, none has been added even since the time of Empedocles and Epicurus two thousand years earlier) and for which other naturalistic evolutionary scenarios remain even more speculative. (p. 270).

No significant details have been added since Darwin? I'm sure the countless graduate students currently preparing for their qualifying exams in evolutionary biology will be interested to hear that they are learning nothing that wasn't known already to Darwin.

Here are some details regarding the emergence of complexity that have been added since Darwin: The mathematical basis of natural selection in the form of population genetics; the unravelling of the genetic code; the identification of the specific proteins comprising numerous complex biological systems and in many cases the underlying genetic basis for these proteins; endless field studies of natural selection in the wild; laboratory experiments in which multi-part systems (usually in microoganisms) can be seen to evolve in a relatively small number of generations; countless computer simulations in which selection acting on random variation can be seen to produce complexity, including "irreducible complexity"; and, best of all, for numerous complex systems impressively detailed descriptions of plausible sequences of intermediates. Systems so explained include the blood clotting cascade, the Krebs cycle, the immune system, the eye and numerous others.

Of course, when confronted with the numerous papers describing such systems, ID people immediately change the argument. Suddenly the problem is not that such scenarios don't exist, it is that they are not detailed enough to satisfy them. Dembski is on record elsewhere as demanding that scientists tell them precisely which genes mutated when, and the precise result this had on the anatomy of the organism. Considering that we are talking about systems that evolved in extinct organisms millions of years ago, that standard seems a bit high. They are free to make this argument if they wish. But it is far different than claiming that no details have been added since Darwin.

Robert Koons, by the way, is a philosopher. He is not a biologist.

Have evolutionary biologists thereby realistically assessed the Darwinian selections mechanism's ability, as actually operating in nature, to produce irreducible complexity? Or have they merely demonstrated the ability of their imaginations to conjure up how a Darwinian process might lead to such systems? Many evolutionary biologists are satisfied with a very undemanding form of ability or capacity-namely
conceivability. So long as they can conceive of a Darwinian or other material pathway to irreducible complexity, material mechanisms trump design. (p. 271) (Emphasis in original).

Truly breathaking. A bravura performance. So much falseness in so few words.

The first thing to point out is that Dembski first made this point in reply to an earlier essay by biologist H. Allen Orr. It began with Orr's review of Dembski's book No Free Lunch, available here. Dembski's reply (in which he first raised this point, along with Orr's reply to the reply, is available here.

In the following quote, ``Behe'' refers to biochemist Michael Behe who first the raised the argument that natural selection can not produce irreducibly complex machines.

Says Orr:

Dembski?s response is to point out that I have merely shown that IC systems can conceivably be built by Darwinism (a point he does not deny), not that such systems were built by Darwinism or even that they were probably built by Darwinism. I am accused, in other words, of having low standards: ?Orr, along with much of the Darwinian community, is satisfied with a very undemanding form of possibility, namely, conceivability.? The problem with this is simple. It was Behe who posed the problem in terms of conceivability versus inconceivability. Behe said that Darwinism could not possibly produce IC systems. Behe spoke of ?unbridgeable chasms.? Behe asked, ?What type of biological system could not be formed by ?numerous, successive, slight modifications??? and then answered, ?A system that is irreducibly complex.? The discussion has, in other words, taken the following form:

BEHE: Darwinism can?t possibly produce IC systems.
ORR: Darwinism can produce IC systems. Here?s how . . .
DEMBSKI: Orr has merely shown that a Darwinian explanation is possible. What a risibly low standard!

I assume the reader will understand if I seem less than eager to continue such a conversation ad infinitum.

Right on. Intelligent design is based entirely on the assertion that certain biological phenomena can not, even in principle, be explained by natural causes. Dembski performs elaborate probability calculations purporting to show that not only can no known natural mechanism account for biological complexity, unknown ones can't do the job either (I'm not kidding. Read section 5.10 of No Free Lunch). So it is certainly relevant to point out that, in fact, complexity can be produced by natural causes.

So do biologists say, ``I can conceive of how this complex system evolved. Problem solved!'' If you think they do, ask yourself what all the research is about. What biologists claim is that the enormous quantity of data that we have is entirely consistent with evolutionary theory. Where questions remain, the problem is a lack of data, not a lack of theoretical robustness. For them, biological complexity seems less mysterious every day.

Of course, Dembski knows that Orr replied to this point. To simply ignore that reply is rather less than honest, wouldn't you say?

Dembski has provided one service, however. If over the next few weeks I find myself hard-up for things to blog about, I know I can just open his book to a random page and find fresh material.


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