Noted Atheist Critiques Neo-Darwinism!

Introduced by Richard Peachey

Thomas Nagel is a professor in the Department of Philosophy and the School of Law at New York University; he is also a fellow of the American Academy of Arts and Sciences. His latest book, published in September 2012, is intriguingly titled Mind & Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False (New York: Oxford University Press).

In this book Nagel makes it clear that he remains an atheist: "I confess to an ungrounded assumption of my own, in not finding it possible to regard the design alternative as a real option. . . . I am not just unreceptive but strongly averse to the idea, as I have said elsewhere." (p. 12)

Though an atheist, Nagel gives credit to Intelligent Design (ID) advocates for contesting the ruling evolutionary paradigm: "Nevertheless, I believe the defenders of intelligent design deserve our gratitude for challenging a scientific world view that owes some of the passion displayed by its adherents precisely to the fact that it is thought to liberate us from religion." (p. 12)

(As you might expect, this book came to my attention through a post on an ID website: <http://www.evolutionnews.org/2012/10/more_from_thoma065131.html>. An article detailing hostile responses to Nagel from other atheists is summarized here: <http://www.firstthings.com/blogs/firstthoughts/2013/03/19/thomas-nagel-and-the-anathema-of-questioning-materialism/>. See also the front-page article on the Nagel controversy in the National Post, March 23, 2013: <http://life.nationalpost.com/2013/03/23/what-has-gotten-into-thomas-nagel-leading-atheist-branded-a-heretic-for-daring-to-question-darwinism/>.)

Nagel appears willing to accept the general concept of large-scale evolution, but his book takes aim at key issues that in his view are not explained by reductionist Neo-Darwinism. He does offer some very tentative, speculative alternative ideas, such as his (impersonal) "teleological" hypothesis, but without a lot of conviction.

The quotes given below illustrate Nagel's scientific and philosophical objections to such evolutionist thinking.


  My target is a comprehensive, speculative world picture that is reached by extrapolation from some of the discoveries of biology, chemistry, and physics—a particular naturalistic Weltanschauung that postulates a hierarchical relation among the subjects of those sciences, and the completeness in principle of an explanation of everything in the universe through their unification. Such a world view is not a necessary condition of the practice of any of those sciences, and its acceptance or nonacceptance would have no effect on most scientific research. For all I know, most practicing scientists may have no opinion about the overarching cosmological questions to which this materialist reductionism provides an answer. Their detailed research and substantive findings do not in general depend on or imply either that or any other answer to such questions. But among the scientists and philosophers who do express views about the natural order as a whole, reductive materialism is widely assumed to be the only serious possibility. (p. 4)

  The starting point for the argument is the failure of psychophysical reductionism, a position in the philosophy of mind that is largely motivated by the hope of showing how the physical sciences could in principle provide a theory of everything. . . . (p. 4)
  The argument from the failure of psychophysical reductionism is a philosophical one, but I believe there are independent empirical reasons to be skeptical about the truth of reductionism in biology. Physico-chemical reductionism in biology is the orthodox view, and any resistance to it is regarded as not only scientifically but politically incorrect. But for a long time I have found the materialist account of how we and our fellow organisms came to exist hard to believe, including the standard version of how the evolutionary process works. The more details we learn about the chemical basis of life and the intricacy of the genetic code, the more unbelievable the standard historical account becomes. This is just the opinion of a layman who reads widely in the literature that explains contemporary science to the nonspecialist. Perhaps that literature presents the situation with a simplicity and confidence that does not reflect the most sophisticated scientific thought in these areas. But it seems to me that, as it is usually presented, the current orthodoxy about the cosmic order is the product of governing assumptions that are unsupported, and that it flies in the face of common sense. (p. 5)

  I would like to defend the untutored reaction of incredulity to the reductionist neo-Darwinian account of the origin and evolution of life. It is prima facie highly implausible that life as we know it is the result of a sequence of physical accidents together with the mechanism of natural selection. We are expected to abandon this naïve response, not in favor of a fully worked out physical/chemical explanation but in favor of an alternative that is really a schema for explanation, supported by some examples. What is lacking, to my knowledge, is a credible argument that the story has a nonnegligible probability of being true. There are two questions. First, given what is known about the chemical basis of biology and genetics, what is the likelihood that self-reproducing life forms should have come into existence spontaneously on the early earth, solely through the operation of the laws of physics and chemistry? The second question is about the sources of variation in the evolutionary process that was set in motion once life began: In the available geological time since the first life forms appeared on earth, what is the likelihood that, as a result of a physical accident, a sequence of viable genetic mutations should have occurred that was sufficient to permit natural selection to produce the organisms that actually exist? (p. 6)
  There is much more uncertainty in the scientific community about the first question than about the second. Many people think it will be very difficult to come up with a reductionist explanation of the origin of life, but most people have no doubt that accidental genetic variation is enough to support the actual history of evolution by natural selection, once reproducing organisms have come into existence. However, since the questions concern highly specific events over a long historical period in the distant past, the available evidence is very indirect, and general assumptions have to play an important part. My skepticism is not based on religious belief, or on a belief in any definite alternative. It is just a belief that the available scientific evidence, in spite of the consensus of scientific opinion, does not in this matter rationally require us to subordinate the incredulity of common sense. That is especially true with regard to the origin of life. (pp. 6-7)

  As I have said, doubts about the reductionist account of life go against the dominant scientific consensus, but that consensus faces problems of probability that I believe are not taken seriously enough, both with respect to the evolution of life forms through accidental mutation and natural selection and with respect to the formation from dead matter of physical systems capable of such evolution. The more we learn about the intricacy of the genetic code and its control of the chemical processes of life, the harder those problems seem. (p. 9)
  Again: with regard to evolution, the process of natural selection cannot account for the actual history without an adequate supply of viable mutations, and I believe it remains an open question whether this could have been provided in geological time merely as a result of chemical accident, without the operation of some other factors determining and restricting the forms of genetic variation. It is no longer legitimate simply to imagine a sequence of gradually evolving phenotypes, as if their appearance through mutations in the DNA were unproblematic—as Richard Dawkins does for the evolution of the eye. With regard to the origin of life, the problem is much harder, since the option of natural selection as an explanation is not available. And the coming into existence of the genetic code—an arbitrary mapping of nucleotide sequences into amino acids, together with mechanisms that can read the code and carry out its instructions—seems particularly resistant to being revealed as probable given physical law alone. (pp. 9-10)

  In thinking about these questions I have been stimulated by criticisms of the prevailing scientific world picture from a very different direction: the attack on Darwinism mounted in recent years from a religious perspective by the defenders of intelligent design. Even though writers like Michael Behe and Stephen Meyer are motivated at least in part by their religious beliefs, the empirical arguments they offer against the likelihood that the origin of life and its evolutionary history can be fully explained by physics and chemistry are of great interest in themselves. Another skeptic, David Berlinski, has brought out these problems vividly without reference to the design inference. Even if one is not drawn to the alternative of an explanation by the actions of a designer, the problems that these iconoclasts pose for the orthodox scientific consensus should be taken seriously. They do not deserve the scorn with which they are commonly met. It is manifestly unfair. (p. 10)
  Those who have seriously criticized these arguments have certainly shown that there are ways to resist the design conclusion; but the general force of the negative part of the intelligent design position—skepticism about the likelihood of the orthodox reductive view, given the available evidence—does not appear to me to have been destroyed in these exchanges. At least, the question should be regarded as open. To anyone interested in the basis of this judgment, I can only recommend a careful reading of some of the leading advocates on both sides of the issue—with special attention to what has been established by the critics of intelligent design. Whatever one may think about the possibility of a designer, the prevailing doctrine—that the appearance of life from dead matter and its evolution through accidental mutation and natural selection to its present forms has involved nothing but the operation of physical law—cannot be regarded as unassailable. It is an assumption governing the scientific project rather than a well-confirmed scientific hypothesis. (p. 11)

[Note: In 2009, atheist Thomas Nagel saw fit to recommend ID advocate Stephen Meyer's book Signature in the Cell: DNA and the Evidence for Intelligent Design as a Times Literary Supplement "book of the year": <http://www.evolutionnews.org/2009/11/signature_in_the_cell_named_on028611.html>.]

  A problem with the most salient current research is that the synthesis of individual components of the genetic material is so heavily controlled and guided by the experimenters that it provides little evidence that the process could have occurred without intelligent guidance. And the crucial question of how these components could have combined into an information-rich coded sequence is left unaddressed. (p. 11)

  Consciousness is the most conspicuous obstacle to a comprehensive naturalism that relies only on the resources of physical science. The existence of consciousness seems to imply that the physical description of the universe, in spite of its richness and explanatory power, is only part of the truth, and that the natural order is far less austere than it would be if physics and chemistry accounted for everything. If we take this problem seriously, and follow out its implications, it threatens to unravel the entire naturalistic world picture. Yet it is very difficult to imagine viable alternatives. (p. 35)

  The explanation by standard evolutionary theory of the purely physical characteristics of organisms is hard enough even if one disregards consciousness. As I have said earlier, the physical and functional complexity of the results imposes very demanding conditions on a reductionist historical explanation. The theory of natural selection, if it is to rely only on the operation of physical law, has to postulate that there is a purely physical explanation of why it is not unlikely that accidental mutations in the genetic material have generated the range of variation in viable phenotypes needed to permit natural selection to produce the evolutionary history that has actually occurred on earth over the past three billion years. Like any historical explanation, it will embody a great deal of contingency, so the particular history of life will not be explained by evolutionary theory alone. But the contingencies and their effects have to be consistent with the physical character of the theory. And to complete the link with physics, the explanation has to suppose that there is a nonnegligible probability that some sequence of steps, starting from nonliving matter and depending on purely physical mechanisms, could eventually have resulted in a replicating molecule capable of all this, embodying a precise code billions of characters long, together with the ribosomes that translate that code into proteins. It is not enough to say, "Something had to happen, so why not this?" I find the confidence among the scientific establishment that the whole scenario will yield to a purely chemical explanation hard to understand, except as a manifestation of an axiomatic commitment to reductive materialism. (pp. 48-49)

  The existence of consciousness is both one of the most familiar and one of the most astounding things about the world. No conception of the natural order that does not reveal it as something to be expected can aspire even to the outline of completeness. And if physical science, whatever it may have to say about the origin of life, leaves us necessarily in the dark about consciousness, that shows that it cannot provide the basic form of intelligibility for this world. There must be a very different way in which things as they are make sense, and that includes the way the physical world is, since the problem cannot be quarantined in the mind. (p. 53)

What we take ourselves to be doing when we think about what is the case or how we should act is something that cannot be reconciled with a reductive naturalism, for reasons distinct from those that entail the irreducibility of consciousness. It is not merely the subjectivity of thought but its capacity to transcend subjectivity and to discover what is objectively the case that presents a problem. (p. 72)
  Thought and reasoning are correct or incorrect in virtue of something independent of the thinker's beliefs, and even independent of the community of thinkers to which he belongs. We take ourselves to have the capacity to form true beliefs about the world around us, about the timeless domains of logic and mathematics, and about the right thing to do. We don't take these capacities to be infallible, but we think they are often reliable, in an objective sense, and that they can give us knowledge. The natural internal stance of human life assumes that there is a real world, that many questions, both factual and practical, have correct answers, and that there are norms of thought which, if we follow them, will tend to lead us toward the correct answers to those questions. It assumes that to follow those norms is to respond correctly to values or reasons that we apprehend. Mathematics, science, and ethics are built on such norms. (p. 72)
  It is difficult to make sense of all this in traditional naturalistic terms. (p. 72)

If physics alone or even a nonmaterialist monism can't account for the later stages of our evolutionary history [i.e., consciousness and reasoning], we shouldn't assume that it can account for the earlier stages. Indeed, when we go back far enough, to the origin of life—of self-replicating systems capable of supporting evolution by natural selection—those actually engaged in research in the subject recognize that they are very far from even formulating a viable explanatory hypothesis of the traditional materialist kind. Yet they assume that there must be such an explanation, since life cannot have arisen purely by chance. (p. 89)
  In fact, that assumption may be based on a confusion. In an important paper, Roger White has argued that the search for an explanation of the origin of life in terms of the nonpurposive principles of physics and chemistry—an explanation that will reveal that the origin of life is not merely a matter of chance but something to be expected, or at least not surprising—is probably motivated by the sense that life can't be a matter of chance because it looks so much as though it is the product of intentional design. (p. 89)

I have argued so far that the reality of consciousness and cognition [including reasoning] cannot be plausibly reconciled with traditional scientific naturalism, either constitutively or historically. I believe that value presents a further problem for scientific naturalism. Even against the background of a world view in which consciousness and cognition are somehow given a place in the natural order, value is something in addition, and it has consequences that are comparably pervasive. (p. 98)

In essence, I agree with Sharon Street's position that moral realism is incompatible with a Darwinian account of the evolutionary influence on our faculties of moral and evaluative judgment. Street holds that a Darwinian account is strongly supported by contemporary science, so she concludes that moral realism is false. I follow the same inference in the opposite direction: since moral realism is true, a Darwinian account of the motives underlying moral judgment must be false, in spite of the scientific consensus in its favor. (p. 105)

  Some comment is called for on the strange, category-jumping nature of this dispute. Street's argument relies on an empirical scientific claim to refute a philosophical position in metaethics. I, even more strangely, am relying on a philosophical claim to refute a scientific theory supported by empirical evidence. But I do not think the movement of thought is inappropriate in either case. Value judgments and moral reasoning are part of human life, and therefore part of the factual evidence about what humans are capable of. The interpretation of faculties such as these is inescapably relevant to the task of discovering the best scientific or cosmological account of what we are and how we came into existence. What counts as a good explanation depends heavily on an understanding of what it is that has to be explained. (p. 106)

This is a revision of the Darwinian picture rather than an outright denial of it. A [natural, i.e., impersonal] teleological hypothesis will acknowledge that the details of that historical development are explained largely through natural selection among the available possibilities on the basis of reproductive fitness in changing environments. But even though natural selection partly determines the details of the forms of life and consciousness that exist, and the relations among them, the existence of the genetic material and the possible forms it makes available for selection have to be explained in some other way. The teleological hypothesis is that these things may be determined not merely by value-free chemistry and physics but also by something else, namely a cosmic predisposition to the formation of life, consciousness, and the value that is inseparable from them. (p. 123)
  In the present intellectual climate such a possibility is unlikely to be taken seriously, but I would repeat my earlier observation that no viable account, even a purely speculative one, seems to be available of how a system as staggeringly functionally complex and information-rich as a self-reproducing cell, controlled by DNA, RNA, or some predecessor, could have arisen by chemical evolution alone from a dead environment. Recognition of this problem is not limited to the defenders of intelligent design. Although scientists continue to seek a purely chemical explanation of the origin of life, there are also card-carrying scientific naturalists like Francis Crick who say that it seems almost a miracle. Crick is led by his reflection on the probabilities to the hypothesis of "directed panspermia"—that Earth was seeded with unicellular life sent from an advanced civilization elsewhere in our galaxy where life had evolved earlier. This depends on the supposition that there were other planets of other stars whose physical environment made the accidental formation of life less unlikely. But Crick acknowledges that there is no basis for confidence about any of these likelihoods. (pp. 123-124)

  Philosophy has to proceed comparatively. The best we can do is to develop the rival alternative conceptions in each important domain as fully and carefully as possible, depending on our antecedent sympathies, and see how they measure up. That is a more credible form of progress than decisive proof or refutation. (p. 127)
  In the present climate of dominant scientific naturalism, heavily dependent on speculative Darwinian explanations of practically everything, and armed to the teeth against attacks from religion, I have thought it useful to speculate about possible alternatives. Above all, I would like to extend the boundaries of what is not regarded as unthinkable, in light of how little we really understand about the world. It would be an advance if the secular theoretical establishment, and the contemporary enlightened culture which it dominates, could wean itself of the materialism and Darwinism of the gaps—to adapt one of its own pejorative tags. I have tried to show that this approach is incapable of providing an adequate account, either constitutive or historical, of our universe. (p. 127)
  However, I am certain that my own attempt to explore alternatives is far too unimaginative. An understanding of the universe as basically prone to generate life and mind will probably require a much more radical departure from the familiar forms of naturalistic explanation than I am at present able to conceive. (p. 127)

I have argued patiently against the prevailing form of naturalism, a reductive materialism that purports to capture life and mind through its neo-Darwinian extension. But to go back to my introductory remarks, I find this view antecedently unbelievable—a heroic triumph of ideological theory over common sense. The empirical evidence can be interpreted to accommodate different comprehensive theories, but in this case the cost in conceptual and probabilistic contortions is prohibitive. I would be willing to bet that the present right-thinking consensus will come to seem laughable in a generation or two—though of course it may be replaced by a new consensus that is just as invalid. The human will to believe is inexhaustible. [end of book] (p. 128)