Tuesday, June 12, 2007

Coyne's Review of Behe

Jerry Coyne, an evolutionary biologist at the University of Chicago, has written a review of Michael Behe's new book for The New Republic (June 18). I generally agree with his assessment.

Like me, Coyne is impressed by how far Behe goes in accepting Darwinian evolution: "Basically, he now admits that almost the entire edifice of evolutionary theory is true: evolution, natural selection, common ancestry." "He even accepts the one fact that most other IDers would rather die than admit: that humans shared a common ancestor with chimpanzees and other apes." As I have indicated in a previous post, I believe this general acceptance of Darwinian science is going to break up the broad coalition that the Discovery Institute has tried to create. Surely, the Biblical creationists are not going to agree that the Intelligent Designer created human beings from apes!

And yet, of course, Behe does argue that Darwinian evolution is severely limited because random mutations cannot create the complex mechanisms of life. But on this point, Coyne shows, Behe's argumentation is weak and even sophistical. For example, he argues that the evolution of precise protein-protein interactions cannot be explained as a product of natural selection working on random mutations, because the simultaneous emergence of three or more mutations to create one protein-protein interaction is too improbable. Coyne rejects this reasoning by indicating that Behe gives no evidence to support his assumption that this could not happen through one mutation after another, involving more and more amino acids, so that a weak interaction favored by natural selection could be followed by ever stronger interactions.

I also agree with Coyne that Behe's rhetoric--and the rhetoric of ID in general--depends on a strategy of negative argumentation, so that one demands that the Darwinian scientists prove the step-by-step pathway of Darwinian evolution for complex biochemical phenomena, but without explaining the step-by-step pathway by which the intelligent designer did this. If one asks the proponents of ID to explain exactly when, where, and how the intelligent designer created irreducibly complex mechanisms, they refuse to answer. If they appear to win the debate, it's only because they have applied standards of proof for Darwinian theory that they could never satisfy themselves.

As Coyne indicates, Behe was made to look foolish when he was cross-examined in 2005 at the Pennsylvania trial for the Dover public school case on teaching ID. Behe was forced to admit, for example, that his definition of science was so loose that it would include astrology. It is remarkable that Behe says nothing about the Dover case in this new book, which confirms the impression of many people that the decision against ID in that case was devastating for the entire ID movement.

Coyne's review can be found here.

A strong critique of Coyne's review by a proponent of evolution and critic of ID--Jason Rosenhouse--can be found here. Although Rosenhouse's criticisms are a little too harsh, he is right to point out that Coyne and other critics of ID are often not as rigorous in their argumentation as they should be.

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