Tuesday, August 30, 2005

Daniel Dennett: the Original Darwinian Fundamentalist

Several other bloggers have commented specifically on Daniel Dennett's attack piece in The New York Times on August 28, 2005. You can read them by following the links on the side to Telic Thoughts, Uncommon Descent (William Dembski) and ID the Future. I do not feel the need to add further specific comments.

However, I note that his article was the number one most emailed article in the Times yesterday, and is already number 3 with a bullet on the 7-day most emailed list. Given how much the readers of the Times appear to be eating it up, I thought it might be a good time to remind people that Daniel Dennett (and his sidekick Richard Dawkins) were the original "Darwinian Fundamentalists" in Stephen Jay Gould's essay entitled "Darwinian Fundamentalism," discussed previously in my posts here and here. For those who do not know, Stephen Jay Gould was a leading paleontologist and evolutionary theorist at Harvard.

Recalling Gould's defense of himself is especially appropriate in light of Dennett's abrasive attack on William Dembski, the Discovery Institute and the intelligent design movement. I do not agree with everything that Gould says, of course, but many of his observations are valuable for obvious reasons.

What is noteworthy is how eloquently Gould argues that random mutation and natural selection are not adequate to explain all the phenomena in the living world. He does not know what all the other mechanisms are, but he believes that other natural mechanisms can explain the complexity of life we see around us. Is it so radical to agree with Gould on his analysis of the limitations of random mutation and natural selection, but not share his faith in the power of other unknown natural mechanisms? And do not high school students deserve more than the diet of Darwin-only dogma that Dennett wants to serve them? Why can't students decide for themselves whether they agree with Dennett, Gould, or neither?

And now over to some extended quotes from Stephen Jay Gould (bold added by me):

Some of these ideas have filtered into the general press, but the uniting theme of Darwinian fundamentalism has not been adequately stressed or identified. . . . Amid the variety of their subject matter, the ultra-Darwinists share a conviction that natural selection regulates everything of any importance in evolution, and that adaptation emerges as a universal result and ultimate test of selection's ubiquity.

. . . .

This strategy of research—the so-called adaptationist program—is the heart of Darwinian biology, and the fervent, singular credo of the ultras.

Since the ultras are fundamentalists at heart, and since fundamentalists generally try to stigmatize their opponents by depicting them as apostates from the one true way, may I state for the record that I (along with all other Darwinian pluralists) do not deny either the existence and central importance of adaptation, or the production of adaptation by natural selection. Yes, eyes are for seeing and feet are for moving. And, yes again, I know of no scientific mechanism other than natural selection with the proven power to build structures of such eminently workable design.

But does all the rest of evolution—all the phenomena of organic diversity, embryological architecture, and genetic structure, for example—flow by simple extrapolation from selection's power to create the good design of organisms? Does the force that makes a functional eye also explain why the world houses more than five hundred thousand species of beetles and fewer than fifty species of priapulid worms? Or why most nucleotides—the linked groups of molecules that build DNA and RNA—in multicellular creatures do not code for any enzyme or protein involved in the construction of an organism? Or why ruling dinosaurs died and subordinate mammals survived to flourish and, along one oddly contingent pathway, to evolve a creature capable of building cities and understanding natural selection?

I do not deny that natural selection has helped us to explain phenomena at scales very distant from individual organisms, from the behavior of an ant colony to the survival of a redwood forest. But selection cannot suffice as a full explanation for many aspects of evolution; for other types and styles of causes become relevant, or even prevalent, in domains both far above and far below the traditional Darwinian locus of the organism. These other causes are not, as the ultras often claim, the product of thinly veiled attempts to smuggle purpose back into biology. These additional principles are as directionless, nonteleological, and materialistic as natural selection itself—but they operate differently from Darwin's central mechanism. In other words, I agree with Darwin that natural selection is "not the exclusive means of modification."

. . . .

My own field of paleontology has strongly challenged the Darwinian premise that life's major transformations can be explained by adding up, through the immensity of geological time, the successive tiny changes produced generation after generation by natural selection. The extended stability of most species, and the branching off of new species in geological moments (however slow by the irrelevant scale of a human life)—the pattern known as punctuated equilibrium—requires that long-term evolutionary trends be explained as the distinctive success of some species versus others, and not as a gradual accumulation of adaptations generated by organisms within a continuously evolving population. A trend may be set by high rates of branching in certain species within a larger group. But individual organisms do not branch; only populations do—and the causes of a population's branching can rarely be reduced to the adaptive improvement of its individuals.

. . . .

Why then should Darwinian fundamentalism be expressing itself so stridently when most evolutionary biologists have become more pluralistic in the light of these new discoveries and theories? I am no psychologist, but I suppose that the devotees of any superficially attractive cult must dig in when a general threat arises. "That old time religion; it's good enough for me." There is something immensely beguiling about strict adaptationism—the dream of an underpinning simplicity for an enormously complex and various world. If evolution were powered by a single force producing one kind of result, and if life's long and messy history could therefore be explained by extending small and orderly increments of adaptation through the immensity of geological time, then an explanatory simplicity might descend upon evolution's overt richness. Evolution then might become "algorithmic," a surefire logical procedure, as in Daniel Dennett's reverie. But what is wrong with messy richness, so long as we can construct an equally rich texture of satisfying explanation?

. . . .

Daniel Dennett's 1995 book, Darwin's Dangerous Idea, presents itself as the ultras' philosophical manifesto of pure adaptationism. Dennett explains the strict adaptationist view well enough, but he defends a miserly and blinkered picture of evolution in assuming that all important phenomena can be explained thereby. His limited and superficial book reads like a caricature of a caricature—for if Richard Dawkins has trivialized Darwin's richness by adhering to the strictest form of adaptationist argument in a maximally reductionist mode, then Dennett, as Dawkins's publicist, manages to convert an already vitiated and improbable account into an even more simplistic and uncompromising doctrine. If history, as often noted, replays grandeurs as farces, and if T.H. Huxley truly acted as "Darwin's bulldog," then it is hard to resist thinking of Dennett, in this book, as "Dawkins's lapdog."

. . . .

"Straight is the gate, and narrow is the way." Fundamentalists of all stripes live by this venerable motto, and must therefore wield their unsleeping swords in constant mental fight against contrary opinions of apostates and opponents (who usually make up a sizable majority—for, as Jesus also noted, "Wide is the gate, and broad is the way, that leadeth to destruction"). The favored fate for the nonelect varies, according to the temperament and power of true believers, from the kindness of simple pity to the refiner's fire of extirpation. But the basic ideological weapon of fundamentalism rarely departs much from the tried and true techniques of anathematization.

Unfortunately, at least for the ideals of intellectual discourse, anathematization rarely follows the dictates of logic or evidence, and nearly always scores distressingly high in heat/light ratio. Anathema also requires an anathemee—and I seem to have been elected. (Whatever my professional contributions to proper Darwinian pluralism, I stand convicted, I suggest, primarily for my efforts to bring the full scope of technical debate, with all its complexities and messiness, but without loss of substance, to general readers.)


At August 30, 2005 7:03 PM, Blogger FzxGkJssFrk said...

John Derbyshire has an article about "teaching the controversy" on National Review Online today, in which he attempts to set a new record for straw-man-arguments-per-paragraph. It could use a good fisking.

At September 10, 2005 2:19 PM, Anonymous PvM said...

"I'm Not Darwin-Only; I'm Science-Only" T-shirt now available.

Evolutionary biologists haven't been "Darwin-only" since..., well, actually, they've never been that way.

Thanks to Skip Evans for the CafePress shop.


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