Meanwhile evolutionary psychologists and anthropologists like Marc Hauser, at
, are studying moral behavior with such precision that they are able to pinpoint the parts of the brain involved in ration-al thinking, emotional reactions, and motivations. And, as always, the context is Darwinian. Why did natural selection push things this way rather than some other way? Harvard University
Exciting times, which makes it all the more remarkable to hear voices from within the mainstream of philosophy questioning the veracity of evolutionary theory. I'll mention three. First there is Alvin Plantinga. Although he teaches at the University of Notre Dame, a Roman Catholic institution, Plantinga is
North America's most distinguished Protestant philosopher of religion. A deeply sincere Calvinist, he has never hesitated to argue for his faith and has done groundbreaking work on questions of knowledge and belief. Even if you disagree with his conclusions, you can admire his skill and learn from his arguments. Plantinga, however, has long harbored a distrust, even an ardent dislike, of evolutionary theorizing in general and of Darwinian thinking in particular. In an essay published in 1999, he wrote, "Consider the role played by evolutionary theory in our intellectual world. Evolution is a modern idol of the tribe; it is a shibboleth distinguishing the ignorant fundamentalist goats from the informed and scientifically acquiescent sheep. Doubts about it may lose you your job. It is loudly declared to be absolutely certain, as certain as that the earth rotates on its axis and revolves around the sun—when it is no such thing at all."
Plantinga is an open enthusiast of intelligent design, the belief that at some points in life's history an intelligent being intervened to move the process along. I am not quite sure whether this makes him a full-blooded creationist, although he has in the past said he does not think it an impossible position. Some supporters of intelligent design, like Phillip E. Johnson, an emeritus professor of law at the
at University of California and author of Darwin on Trial (Regnery, 1991), seem to reject all forms of evolution. Others, like Michael J. Behe, a professor of biological sciences at Berkeley and author of Darwin's Black Box: The Biochemical Challenge to Evolution (Free Press, 1996), seem to accept a lot of common descent and might even be called theistic evolutionists, meaning that they think God guides the course of continuous development. Wherever Plantinga stands on this spectrum, he stands with the intelligent-design theorists in strongly emphasizing what they see as the falsity of Darwinian evolutionary biology. Lehigh University
Why does Plantinga feel this way? In his view, Darwinism implies that there is and can be no direction in life's history. All change is a function of randomly appearing new variations (mutations) that are then sifted by the opportunistic mechanism of natural selection. Although new variations are not uncaused, they do not appear according to need. As Darwin himself argued, to think otherwise is to illicitly bring in a directing God. The late Harvard paleontologist Stephen Jay Gould used to pun that the arrival of the human species was entirely an accident brought on by our lucky stars—a comet that hit the earth 65 million years ago, wiping out the dinosaurs and allowing for the rise of mammals. It is precisely that kind of thinking to which Plantinga is opposed.
Plantinga's reactions to evolutionary biology are disappointing but understandable. Disappointing because, generally speaking, Calvinists are favorable to science: It is all part of God's sovereignty, and it is our task to discover his immutable laws. As the Victorians used to say about sexual intercourse, if God decided that we should reproduce in such a disgusting way, then it is for us to accept this fact and put it in context. The same can be said about Darwinian evolution. Plantinga's views are understandable because philosophy today tends to be very secular, and there is a lot of sympathy for the claims of the so-called New Atheists—Richard Dawkins, Daniel C. Dennett, Sam Harris, Christopher Hitchens—that if you are a Darwinian, then you ought to be at least an agnostic, if not an outright atheist. Philip Kitcher, a professor of philosophy at Columbia University and author of Living With Darwin: Evolution, Design, and the Future of Faith (Oxford University Press, 2007), has spoken of Plantinga's decision to blurb Johnson's book as revealing "a combination of Schwärmerei [excessive sentiment] for creationist doctrine and profound ignorance of relevant bits of biology," which has caused Plantinga to put his brain "in cold storage."
Much more surprising is the position of the
philosopher Thomas Nagel, who has established himself right at the top of the field thanks to a long series of dazzling essays on topics as diverse as the thinking apparatus of a bat and the nature of sexual perversion. Although he states firmly that he does not believe in a deity, he has now come out against Darwinism. If Nagel is not a supporter of intelligent design, one wonders why he says what he does. He has endorsed a book by Stephen C. Meyer, Signature in the Cell: DNA and the Evidence for Intelligent Design (HarperOne, 2009), naming it one of the top books of 2009 in the Times Literary Supplement. New York University
In a recent article, Nagel argues that it is proper to teach intelligent design in the classroom. Doubting the Darwinian claim that the sources of variation are undirected, Nagel quotes Behe as an authority. "Are the sources of genetic variation uniformly random or not? That is the central issue, and the point of entry for defenders of ID," Nagel writes. He goes on to tell us that Behe's recent book, The Edge of Evolution, examines the "currently available evidence about the normal frequency and biochemical character of random mutations in the genetic material of several organisms."
Nagel leaves the reader with the impression that Behe's concerns are well taken. Behe, according to Nagel, argues that "widely cited examples of evolutionary adaptation, including the development of immunity to antibiotics, when properly understood, cannot be extrapolated to explain the formation of complex new biological systems. These, he claims, would require mutations of a completely different order, mutations whose random probability, either as simultaneous multiple mutations or as sequences of separately adaptive individual mutations, is vanishingly small."
Like Plantinga, Nagel is skeptical about the whole evolutionary enterprise. Suppose someone says that doubting evolutionary theory is equivalent to thinking the earth is flat. Nagel writes: "This seems to me, as an outsider, a vast underestimation of how much we do not know, and how much about the evolutionary process remains speculative and sketchy." He goes on to tell us that those who think we are now well on the track to understanding the mechanisms of evolution are wrong: "Nothing close to this has been done." And in a comment to which I shall refer below, he writes: "A great deal depends on the likelihood that the complex chemical systems we observe arose through a sufficiently long sequence of random mutations in DNA, each of which enhanced fitness. It is difficult to find in the accessible literature the grounds for evolutionary biologists' confidence about this."
Naturally the origin-of-life issue is raised—and found wanting ("a complete scientific mystery at this point"). It is hardly surprising, therefore, that Nagel thinks that evolutionary biology is more happily accepted by nonbelievers than by theists: "This is just common sense."
Jerry Fodor, no less distinguished than Nagel and Plantinga, is well known for his claim that the mind is composed of separately functioning modules. And he, too, has taken to criticizing Darwinian theory, first in an article in the London Review of Books and now in What Darwin Got Wrong. Fodor finds something deeply flawed in contemporary evolutionary thinking: "An appreciable number of perfectly reasonable biologists are coming to think that the theory of natural selection can no longer be taken for granted. This is, so far, mostly straws in the wind; but it's not out of the question that a scientific revolution—no less than a major revision of evolutionary theory—is in the offing."
To Fodor the notion of natural selection is flawed. He has long been on record arguing that metaphors in science are misleading, and that they must be eliminated as science matures. In the case of Darwinism, we have an analogy or metaphor at work, between the artificial selection that breeders use when they improve livestock—shaggier sheep, beefier cows—and the process of differential reproduction that Darwinians think leads to evolutionary change (in the direction of adaptive advantage). Fodor believes that differential reproduction illicitly brings mind into the natural process:
The present worry is that the explication of natural selection by appeal to selective breeding is seriously misleading, and that it thoroughly misled
. Because breeders have minds, there's a fact of the matter about what traits they breed for; if you want to know, just ask them. Natural selection, by contrast, is mindless; it acts without malice aforethought. That strains the analogy between natural selection and breeding, perhaps to the breaking point. What, then, is the intended interpretation when one speaks of natural selection? The question is wide open as of this writing. Darwin
Fodor argues that this problem is insoluble. Fortunately we need not worry much, because in going with selection, evolutionists have been grasping the wrong end of the stick. In his view, today's proper-thinking evolutionary biologists are finding that it is all in the variations anyway. All evolutionary change comes about through the genes and their development. Even if natural selection were at work, Fodor argues, the most it could do is clean up afterward.
What does one say about these critics? One could certainly pick apart individual things, for instance Fodor's claims about selective breeding versus natural selection. The very last thing that Darwin and his followers are trying to do is put mind into nature. In both artifice and nature, some organisms are going to reproduce and others are not, and the reasons for that are (on average) going to be connected to the different features of the winners and losers. To say that a speckled moth is less likely to be eaten by a robin than a dark moth, because the robin can less easily see the speckled moth against the lichen-covered tree, is to say nothing about God or any other conscious being.
One could also pick up on the fact that neither Plantinga nor Nagel seems to have the slightest awareness of the scientific criticisms that have been launched against intelligent design. Every example that supporters of intelligent design produce to suggest that natural causes are not adequate—the bacterial flagellum, the blood-clotting cascade—has been shown to be the exquisite end result of evolution. And one could certainly groan at the tired suggestion that Darwinians are unaware of or threatened by developments in evolutionary development. No evolutionary biologist, least of all Sean Carroll, suggests that one day the eye just appeared. However the new sources of variation play out, selection is going to be there right along with them.
But rather than work over the details, I want to draw attention to the way this crop of critics ignores evolutionary biology—aside from the kind of cherry-picking in which Fodor engages. Nagel may sneer about the failure to find "accessible literature" that answers his worries. In what part of the library was he doing his literature search? Where, for example, is any discussion of the Grants' work on the Galápagos finches? What about a detailed look at the new scholarship that is challenging earlier thinking about the evolution of bipedalism? What about the discoveries of molecular biology and of the similarities (homologies) between humans and fruit flies? And why no mention of Marc Hauser and his work uncovering the secrets of moral thinking? There is a deafening silence on those and other issues. Fodor, Nagel, and Plantinga don't need to turn themselves into biochemists, but some awareness of the issues and advances would not be entirely misplaced.
This total lack of interest in the science is surely suggestive. The critics are being driven by other, for them deeper, concerns… Michael Ruse directs the program in the history and philosophy of science at
. His latest book, Science and Spirituality: Making Room for Faith in the Age of Science, was just published by Cambridge University Press. He contributes to The Chronicle Review's blog, Brainstorm. Florida State University