Assault on evolution

Dembski argued that we should infer intelligent design when we see what he calls "specified complexity." We detect intelligent design in events that are highly improbable (thus complex) and that also correspond to some independently given pattern (thus specified). For example, we might see some Scrabble letters on a table in a sequence such as BDWSFCHJDMB, which would be improbable but not specified. Or we might see a sequence such as THE, which would be specified but not improbable. In neither case could we reasonably infer intelligent design. But we could rightly make a design inference if we saw METHINKSITISLIKEAWEASEL, because this is both improbable and specified; it looks as if some intelligent human being has arranged the letters.

If a detective decides that our deceased woman's death was not accidental or from natural causes but, rather, the result of a murderer's plot, he is inferring intelligent design from specified complexity. According to Dembski, we make similar inferences every day of our lives when we conclude that something has occurred because of someone's purposeful plan.

You can see where Dembski is headed. The genetic information in DNA that governs all life is stored in a highly complex and highly specified sequence of chemicals called nucleotide bases. If God really did create Adam and Eve from the dust of the earth, that would be a miracle. But wouldn't it be equally miraculous if God created the genetic code that controls the development of human beings as well as all other living beings?

Yet the theory of a miracle-working designer seems to lead to more questions than it answers. If evolution doesn't occur, does the designer miraculously intervene to separately create every species of life and every irreducibly complex mechanism in the living world? If so, exactly when, where and how does that happen? Did the designer create the first human beings as fully formed adults, bellybuttons and all? And by what observable causal mechanisms does the designer execute these miraculous acts? How would one formulate falsifiable tests for such a theory? Proponents of IDT refuse to answer such questions, because it puts them at a rhetorical disadvantage. It's far easier for them to take a purely negative position in which they criticize Darwinian theory without defending their own.

Jonathan Wells understands this strategy very well. Like Behe and Dembski, Wells is sponsored by the Discovery Institute to promote IDT as an alternative to Darwinian science. In his new book, "Icons of Evolution," Wells shrewdly employs a purely negative approach -- attacking weaknesses in Darwinian theory while refusing to defend intelligent design in any positive way. He encourages the reader to infer that since Darwinian evolution hasn't been absolutely demonstrated, creation by an intelligent designer wins by default as the only reasonable alternative. However, the standards of proof Wells demands of Darwinian biology are so unreasonably high that he could never satisfy himself if he had to argue for intelligent design.

If we remember nothing else from our biology textbooks, many of us remember what Wells dubs the "icons of evolution," the standard examples used to demonstrate Darwin's theory. These include the peppered moths that became vulnerable to bird predators when they lost their camouflage as a result of air pollution that blackened tree trunks, the various species of finches in the Galápagos Islands that evolved for diverse ecological niches, the similarity between the embryos of radically different species and the pictures showing the gradual evolution of humans from apes. Wells argues that each of these standard textbook stories of evolution and many more are either distortions of the truth or complete lies.

Next Page: Solid evidence of evolution or dodgy science?

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