First Things RSS Feed - William A. Dembski

The Mind and the Brain: Neuroplasticity and the Power of Mental Force

Thu, 01 May 2003 00:00:00 -0400

In the epilogue to Jeffrey Schwartz and Sharon Begley’s The Mind and the Brain: Neuroplasticity and the Power of Mental Force , we read: “Finally, after a generation or more in which biological materialism has had neuroscience—indeed, all the life sciences—in a chokehold, we may at last be breaking free . . . . Biological materialism did and does have real-world consequences. We feel its reach every time a pharmaceutical company tells us that, to cure shyness (or ‘social phobia’), we need only reach for a little pill . . . . Biological materialism is nothing if not appealing. We need not address the emotional or spiritual causes of our sadness to have the cloud of depression lift; we need not question the way we teach our children before we can rid them of attention deficit disorder.”

Continue Reading »

Conservatives, Darwin & Design: An Exchange

Wed, 01 Nov 2000 00:00:00 -0500

One sign of the intellectual confusion among conservatives these days is that they cannot decide what to think about Charles Darwin. Some conservatives (such as Charles Murray and James Q. Wilson) appeal to Darwinian biology as showing how moral order is rooted in human nature. But others (such as William F. Buckley, Jr. and Andrew Ferguson) reject Darwinism as a form of scientific materialism that is morally corrupting.

Consider, for example, the conservative reaction to Francis Fukuyama’s book The Great Disruption . Fukuyama used a Darwinian theory of human social behavior to support the conservative view that there really is a human nature that sets norms for social order, in contrast to the common view of cultural relativists that social rules are arbitrary constructions of cultural life. Fukuyama’s book provoked a passionate rebuttal in the Weekly Standard from Andrew Ferguson, who warned conservatives that Darwinian science promotes a crude materialism that denies the freedom and dignity of human beings as moral agents. Peter Lawler, writing in Modern Age , agreed with Ferguson and even denounced Fukuyama as a “teacher of evil.” Conservatives like Ferguson and Lawler are at least partially correct, because some Darwinians (Richard Dawkins, for example) do interpret Darwinian theory as dictating a reductionistic view of human beings as governed by their “selfish genes.” I think Fukuyama ultimately has the better argument, however, because he sees that Darwinian biology rightly understood confirms our commonsense view of human beings as naturally social animals whose social life depends on a natural moral sense, which thus supports the conservative view of human nature.

But before I can defend the goodness of Darwinism as sustaining a conservative view of human nature and moral order, I must defend its truth. Some conservatives have been persuaded by Phillip E. Johnson, Michael J. Behe, William A. Dembski, and other proponents of “intelligent design theory” that Darwin’s theory of evolution by natural selection has little support in evidence and logic, and that Darwinians stubbornly refuse to recognize the evidence of “intelligent design” in the living world as pointing to a divine Creator.

I agree that conservatives should take seriously the good criticisms of Darwinian biology offered by people like Johnson, Behe, and Dembski. I do not assert that Darwinian theory can be demonstrated with the precision and certainty that would leave no room for reasonable doubt. I only assert that Darwinian theory is supported by the preponderance of the evidence and arguments. In fact, that is all Darwin himself ever claimed for his position. Moreover, although I do not think we can reason by logical inference from ordinary experience to the existence of a Creator, a Darwinian view of the living world as governed by natural laws is at least compatible with a theistic faith in the Creator as the supernatural source of those natural laws.

Darwin acknowledged that there were many serious objections to his theory of descent with modification through natural selection. In The Origin of Species , he devoted more than one“third of his argument to considering the “difficulties” for his theory. He admitted that some of the objections “are so serious that to this day I can hardly reflect on them without being in some degree staggered.” And yet he answered those objections and insisted that his theory would emerge as highly “probable” if one considered the “facts and arguments” in its favor.

Darwin recognized that evolutionary biology has all the difficulties that come from being a historical science concerned with unique events in the past that cannot be directly observed or experimentally replicated in the present. The record of the past”such as the geological record of fossils”is incomplete, and therefore Darwin’s theory of evolutionary history cannot be proven conclusively. Phillip Johnson exploits this limitation”one inherent in any historical science”by demanding complete historical and experimental evidence for Darwin’s theory. He can then conclude that the theory is unsupported by the evidence whenever the evidence is incomplete, as it always will be. But this rhetorical strategy is unreasonable in denigrating the impressive evidence for Darwin’s theory, evidence that has been well surveyed by Kenneth Miller in his recent book, Finding Darwin’s God , which defends Darwinism against Johnson, Behe, and other critics.

Indeed, in Darwin’s Black Box , Michael Behe concedes that there is enough evidence to support the Darwinian conclusion that all species, including human beings, arose from a common ancestor by descent with modification by natural selection. But he maintains that one kind of biological system cannot be explained by Darwin’s theory”namely, any system that is “irreducibly complex.”

An “irreducibly complex” system, Behe explains, is “a single system composed of several well“matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning.” Such a complex system cannot be produced by natural selection working gradually to improve simpler systems, because “an irreducibly complex system cannot be produced directly (that is, by continuously improving the initial function, which continues to work by the same mechanism) by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional.”

Behe’s favorite analogy is a mousetrap, which is an irreducibly complex system because it could not perform its function of catching mice if any one of its interlocking parts were absent. From observing the mousetrap, we can infer a human designer as its creator. Similarly, Behe argues, from observing the irreducible complexity of biomolecular systems, we can infer that they were created by a divine designer rather than by natural selection working on random variation in evolutionary history. (William Dembski has extended this reasoning in using mathematical probability theory to lay out the formal criteria for detecting “design” when we see “patterned improbability” or “specified complexity.”)

As the primary evidence for his position, Behe describes six kinds of biomolecular mechanisms”bacteria moved by a flagellum, cells moved by cilia, blood clotting, cellular transport systems, the immune system, and the biosynthesis of proteins and nucleic acids. In each case, he shows first the great complexity of these systems, and then claims that no scientist has succeeded in explaining clearly and precisely how these complex biochemical systems emerged gradually by Darwinian evolution. Scientists should conclude from this, Behe insists, that the only way to explain such biological complexity is to recognize it as an effect of “intelligent design” by a Creator.

The biologists who reviewed Behe’s book had to admit that he was right in claiming that evolutionary biologists have not explained the exact evolutionary pathways for the six biomolecular mechanisms he considers. But as the reviewers indicated, this does not show that such evolutionary pathways do not exist; it only shows our ignorance. Developing such an explanation in the future remains a realistic possibility, claim the scientists, and so Behe’s argument from ignorance is weaker than he allows.

Behe often accepts the Darwinian explanations for the origin of anatomical structures. And even at the level of molecular biology, he sometimes accepts Darwinian theory as adequate. For example, he agrees with the Darwinian explanation for the origin of hemoglobin”the protein that carries oxygen in the blood”as having evolved through a natural modification of the simpler protein myoglobin. Here, he admits, “the case for design is weak.” Yet as long as there are other biological phenomena that are not explained so clearly by natural evolutionary causes, Behe thinks he can infer “intelligent design.”

It appears, then, that Behe’s argument is constructed so that it could never be falsified. Even as he concedes that Darwinian scientists can explain the evolutionary origin of many biochemical mechanisms, Behe can always say that whatever remains unexplained is the evidence for “intelligent design.” But since science will never succeed in explaining everything, he can never be refuted.

Moreover, Behe, Dembski, and the other proponents of “intelligent design theory” employ a fundamentally fallacious line of reasoning in their equivocal use of the term “intelligent design.” Dembski claims that “intelligent design . . . is entirely separable from creationism.” He explains: “Intelligent design is detectable; we do in fact detect it; we have reliable methods for detecting it; and its detection involves no recourse to the supernatural. Design is common, rational, and objectifiable.”

If this is what he means by “intelligent design,” then any rational person should accept it, and it would not be very controversial. In fact, most of what Dembski says in his book The Design Inference about how we infer design from “specified complexity” is an uncontroversial account of how we detect design by humanly intelligent agents. Up to this point, there is indeed “no recourse to the supernatural.” But clearly Dembski wants more than that. He writes: “The world is a mirror representing the divine life. The mechanical philosophy was ever blind to this fact. Intelligent design, on the other hand, readily embraces the sacramental nature of physical reality. Indeed, intelligent design is just the Logos theology of John’s Gospel restated in the idiom of information theory.” This leads Dembski to conclude that “Christ is indispensable to any scientific theory.” Here the “recourse to the supernatural” is clear.

This confusion in “intelligent design theory””both affirming and denying “recourse to the supernatural””arises from equivocation in the use of the term “intelligent design.” Both Dembski and Behe speak of “intelligent design” without clearly distinguishing “ humanly intelligent design” from “ divinely intelligent design.” We have all observed how the human mind can cause effects that are humanly designed, and from such observable effects, we can infer the existence of humanly intelligent designers. But insofar as we have never directly observed a divine intelligence (that is, an omniscient and omnipotent intelligence) causing effects that are divinely designed, we cannot infer a divinely intelligent designer from our common human experience.

Behe is right that from an apparently well“designed mousetrap we can plausibly infer the existence of a humanly intelligent designer as its cause, because we have common experience of how mousetraps and other artifacts are designed by human minds. (As Dembski indicates, common experience also allows us to identify some animals as intelligent designers.) But from an apparently well“designed organic process or entity we cannot plausibly infer the existence of a divinely intelligent designer as its cause, because we have no common experience of how a divine intelligence designs things for divine purposes.

If something appears to be intelligently designed, and we cannot plausibly explain it either as designed by human intelligence or as a product of Darwinian causes, then we are just ignorant of the causes. The writing of people like Dembski and Behe is instructive in pointing to such cases of ignorance. To assume, in such a case, that the cause is not divine requires faith in materialism. To assume that the cause must be divine requires faith in theism. Both positions”materialism and theism”ultimately rest on faith, because they go beyond common human experience. Through their equivocal use of the term “intelligent design,” the proponents of intelligent design theory hide their inescapable appeal to faith. (Of course, the scientific materialists often try to hide their own appeal to faith.) Contrary to what the intelligent design theorists claim, we cannot move by ordinary experience and logic alone to any inference about a divinely intelligent designer conforming to “the Logos theology of John’s Gospel.” For that we need faith.

Darwinism is no threat to such theistic faith. Darwinian science must ultimately appeal to the laws of nature as the final ground of explanation; but to ask why nature has the laws that it does is to move beyond nature to nature’s God. Atheistic Darwinians like Richard Dawkins cannot deny the theistic faith in God as the First Cause without assuming a materialistic faith that goes beyond the evidence and logic of empirical science. Darwin himself openly confessed that questions about first causes”the origin of life itself or the origin of the universe as a whole”pointed to mysteries that might be forever beyond his science. Thus, Darwinism is compatible with belief in the biblical God.

But is Darwinism compatible with faith in God as the giver of the moral law? That question points to the deeper issue at stake here, because most of the opposition to Darwinian theory among conservatives is motivated not by a purely intellectual concern for the truth or falsity of the theory, but by a deep fear that Darwinism denies the foundations of traditional morality by denying any appeal to the transcendent norms of God’s moral law. John G. West, Jr. is the Associate Director of the Discovery Institute’s Center for the Renewal of Science and Culture, which has sponsored many of the critics of Darwinism. He explains the conservative motivation for this position when he warns that Darwinism promotes a “scientific materialism” that subverts all traditional morality. “If human beings (and their beliefs) really are the mindless products of their material existence, then everything that gives meaning to human life”religion, morality, beauty”is revealed to be without objective basis.”

Similarly, Ferguson, in his attack on Fukuyama, warns conservatives to be suspicious of modern natural science. Insisting on a stark opposition between the scientific study of natural causes and the human experience of moral freedom, he argues that human beings as “autonomous selves” are free from the determinism of nature that is presupposed by Darwinian science. As an alternative to the “materialistic myth of the new science,” Ferguson suggests that conservatives should appeal to “the older myths” of free will and natural law as the intellectual foundation for their moral and political thought.

But Ferguson’s separation between biological nature and human freedom is a false dichotomy. A biological explanation of human nature does not deny human freedom if we define that freedom as the capacity for deliberation and choice based on one’s own desires. Darwinian science shows, for example, that there are natural differences on average in the behavioral propensities of men and women, and surely conservatives are right to argue that it is foolish for public policies to ignore those natural differences between the sexes. Unlike those on the left, conservatives should recognize”contrary to Ferguson”that human beings are not “autonomous selves” if that means being utterly liberated from their natural sexual identity.

Furthermore, Ferguson’s exhortation to conservatives to rely on “old myths” as an alternative to natural science is very bad advice indeed, because this would confirm the complaint of those on the left that conservatism requires an irrational commitment to traditional myths with no grounding in reason or nature. Like Fukuyama, James Q. Wilson, and other Darwinian conservatives, I would argue that conservatives should see that Darwinian views of human nature provide scientific support for the traditional idea of natural moral law. Human beings really are naturally social and moral animals, and therefore we can judge social life by how well it conforms to the natural needs and desires of the human animal. Natural law is not a “myth.” It is a rationally observable and scientifically verifiable fact.

Earlier this year, in a special issue of National Review devoted to “The New Century,” Charles Murray predicted: “The story of human nature as revealed by genetics and neuroscience will be Aristotelian in its philosophical shape and conservative in its political one.” I agree, because I see modern biological studies of human nature and morality as a continuation of an intellectual tradition begun by Aristotle that favors a conservative view of social order as rooted in natural human propensities.

Aristotle was a biologist, and he concluded from his biological studies of animal behavior that all social cooperation arises ultimately as an extension of the natural impulses to sexual coupling and parental care of the young. Thomas Aquinas continued Aristotle’s biological reasoning about ethics in defending his idea of “natural law” or “natural right.” “Natural right,” Aquinas declared, “is that which nature has taught all animals.” Sexual mating and parental care belong to natural law because they are natural inclinations that human beings share with some other animals. And although the rationality of human beings sets them apart from other animals, human reason apprehends natural inclinations such as mating and parenting as good. Marriage as constituted by customary or legal rules is uniquely human, Aquinas indicates, because such rules require a cognitive capacity for conceptual reasoning that no other animals have. But even so, such rules provide formal structure to desires that are ultimately rooted in the animal nature of human beings.

Although the idea of natural law is most commonly associated with Catholic moral philosophy, the same idea can be found in Protestant Christianity and Judaism. Both John Calvin and Martin Luther spoke of the natural law as the moral law written into the hearts of human beings. In Judaism, a similar teaching arises in the ancient rabbinical tradition of natural law as the “Noahide laws” that God gave to Noah and his descendants, a moral law binding on all humanity by virtue of a universal human nature. David Novak has elaborated the arguments for this Jewish understanding in his recent book, Natural Law in Judaism .

Adam Smith continued in this same tradition of ethical naturalism in The Theory of Moral Sentiments . Smith showed how ethics could be rooted in the moral sentiments of human nature and the natural inclination to sympathy. Although we can have no direct experience of the feelings of others, Smith believed, we can by sympathy imagine what we would feel in similar circumstances. We take pleasure not only in sharing the feelings of others, but also in knowing that they share our feelings. As formed by nature for social life, human beings are born with a strong desire to please and a strong aversion to offending their fellow human beings. Smith inferred from this that we are inclined to act in such a way as would be praised by others. We judge the conduct of others as proper if it harmonizes with what we would feel and do in their circumstances, and likewise we judge our conduct as proper if it is such as would be approved of by others.

Darwin in The Descent of Man adopted this Smithian teaching about sympathy and the natural moral sentiments in developing his biological theory of the moral sense as rooted in human nature. A few years ago, James Q. Wilson’s book The Moral Sense showed how this Aristotelian“Smithian“Darwinian tradition of moral reasoning has been confirmed by modern social scientific research. By bringing together the philosophic tradition of ethical naturalism from Aristotle to Smith and the scientific tradition of Darwinian reasoning about human nature, conservatives could base their moral and political thought on what I have called “Darwinian natural right.”

Conservatives influenced by Leo Strauss might object to this idea by citing Strauss’ claim that Aristotelian natural right depends on a teleological view of the universe that is denied by modern science. But I would argue that Aristotle’s teleology is primarily biological, and so the question is whether teleology is necessary for living nature. Aristotle’s biological teleology is not a cosmic teleology but an immanent teleology, and this immanent teleology is confirmed by Darwinism. Darwin’s principle of natural selection explains the adaptation of species without reference to any forces guiding nature to secure a cosmic scale of perfection. Yet, although the evolutionary process does not serve goals, the organisms emerging from that process do.

Darwin’s biology does not deny”rather it reaffirms”the immanent teleology displayed in the striving of each living being to fulfill its species“specific ends. Reproduction, growth, feeding, healing, courtship, parental care of the young”these and many other activities of animals are goal“directed. Biologists cannot explain such processes unless they ask about their ends or purposes, and thus they must still look for “final causes.” In arguing for the immanent teleology of biological phenomena, I agree with Leon Kass that a crucial part of a “more natural science” would be a Darwinian understanding of teleology as rooted in “the internal and immanent purposiveness of individual organisms.” Explaining natural right as rooted in human biological nature would move towards what Strauss identified as “comprehensive science,” a science of nature that would include the ethical striving of human nature as part of the natural world.

Adopting a Darwinian view of human nature and ethics would have both theoretical and practical benefits for conservatism. The theoretical benefit in a Darwinian conservatism is that an Aristotelian conception of natural right rooted in a Darwinian understanding of human nature would provide a solid intellectual basis for conservative political thought. Oddly enough, this point becomes clear if one reads Peter Singer’s new book, A Darwinian Left . Singer recognizes that the traditional left has rejected the idea of a fixed human nature and affirmed the malleability and perfectibility of humankind, because the left has wanted to radically transform human life by changing the social and economic conditions that supposedly determine human history. Like Ferguson, the traditional left has assumed that human history transcends natural history. The collapse of Marxist and other socialist regimes in the twentieth century seemed to confirm, however, the prediction of Ludwig von Mises in 1922 that socialism would fail because it was contrary to human nature. Singer’s response is to try to persuade his fellow leftists to adopt a Darwinian view of human nature. “A Darwinian left,” he explains, would accept “that there is such a thing as human nature, and seek to find out more about it, so that policies can be grounded on the best available evidence of what human beings are like.” But the strain in his argument is clear when he confesses, “In some ways, this is a sharply deflated vision of the left, its utopian ideas replaced by a coolly realistic view of what can be achieved. That is, I think, the best we can do today.” In fact, most of what he suggests as part of his “sharply deflated vision of the left” would be acceptable to conservatives, who have long assumed that conformity to human nature is a fundamental goal of good social policy. Without realizing what he has done, Singer implicitly shows how a Darwinian understanding of human nature supports a conservative view of social order.

Conservatives such as Ferguson, who reject a theoretical foundation in human nature, must ultimately appeal to “myth” as their final ground of judgment, which follows the lead of such conservative thinkers as Richard Weaver who spoke of the “metaphysical dream” of transcendent order as a poetic creation necessary for any culture. The danger here is that conservatism begins to look like a Burkean Nietz scheanism, in which the moral order of society requires mythic traditions as noble lies that hide the ugly truth of nihilism.

Religious conservatives might rely on God’s moral law as the transcendent ground of their conservatism; but if they see no natural law rooted in human nature, they have no common ground of moral discourse with those who do not share their particular religious faith. David Novak has said that “natural law is that which makes Jewish moral discourse possible in an intercultural world.” The same could be said about the moral discourse of Catholics and Protestants.

The practical benefit in a Darwinian conservatism is that it would sustain conservative reasoning about public policy. Although Darwinism cannot prescribe specific policies, it can remind us of the propensities of human nature to which any successful policy must conform. Consider, for example, the issues of policy associated with crime, family life, and military service. Violent crime is committed mostly by young unmarried men, and thus preventing or controlling such crime depends on understanding the biological nature of young men and the universal need in every society to channel their male propensities into socially acceptable behavior. The stability of family life is fundamental for every society because the dependence of the young on parental care is a natural characteristic of the human animal, and thus every good society must regulate sexual mating, conjugal bonding, and parental attachment to children to secure the natural ends of family life. Training for military combat is predominantly a young male activity, and the natural differences in the temperament of men and women will always impede any attempt to eliminate sexual differences in military service. Although cultural and historical circumstances create great variability in the behavioral patterns of crime, family life, and military service, conservative policies should recognize the natural inclinations of human biology that constrain policy choices in these areas of life.

As Aristotle and Darwin recognized, deciding such practical issues requires the prudence that can determine what would be best for particular situations in particular societies. The biology of human nature is not about natural necessities that hold in all cases, but about natural propensities that hold in most cases. A Darwinian conservatism would therefore respect the variability in human affairs. And yet the universality of human biological nature would allow us to judge divergent policies of action by how well they nurture the natural desires and capacities of human beings as social animals.

We can anticipate that the future will bring wondrous advances in the scientific study of human nature. These advances will come from many fields of biology, such as genetics, neurobiology, animal behavior, developmental biology, and evolutionary theory. If conservatism is to remain intellectually vital, conservatives will need to show that their position is compatible with this new science of human nature.

That’s why conservatives need Charles Darwin.

Larry Arnhart is Professor of Political Science at Northern Illinois University. His most recent book is Darwinian Natural Right: The Biological Ethics of Human Nature.

Continue Reading »

Nonzero: The Logic of Human Destiny

Tue, 01 Aug 2000 00:00:00 -0400

In Nonzero Robert Wright argues convincingly that certain patterns in biological and cultural evolution cannot properly be attributed to contingency or accident but rather point to an underlying teleology”for him, a fully naturalized teleology. Most teleologies of the past have looked to some entity or principle beyond the strictly material and physical. Bossuet’s universal history guided by providence, Hegel’s phenomenology of spirit, Bergson’s élan vital, and Teilhard de Chardin’s omega point”all invoked quasi“mystical elements. Wright wants none of this. Instead, he wants a teleology acceptable to the most hard“core of scientific materialists.

Wright’s naturalized teleology unites two theories: Darwinism and game theory, the latter a mathematical theory widely employed in the social sciences (especially economics). Wright is neither a biologist nor a mathematician, and he never ex plains or justifies these theories, being content to presuppose them and apply them as broadly as possible.

Wright’s naturalized teleology works as follows. Organisms, whether evolving biologically or culturally, face pressures that can hinder them from leaving offspring. For biological evolution the offspring are genes; for cultural evolution they are “memes” (this coinage by Richard Dawkins denotes a basic unit of cultural information, e.g., a religious doctrine). The essential characteristic of organisms is reproduction, and what they reproduce are genes (through biological reproduction) or memes (through cultural dissemination). Genes and memes, according to Wright, constitute an organism’s enduring heritage.

Now the question most on Wright’s mind is how specific genes and memes emerge, become prominent, and ultimately dominate a gene or meme pool. For Wright the answer always devolves to the interplay between Darwinian natural selection, zero“sum games, and non“zero“sum games. According to Wright there is a well“defined logic to this interplay. Initially there’s a zero“sum game, that is, an interaction between organisms where one’s loss is another’s gain. Zero“sum games place enormous stress on an organism and lead it to seek support from fellow organisms that are, as Wright puts it, “in the same boat.”

Organisms in the same boat, facing common external pressure, do best by rowing in sync”in other words, by cooperating. In the language of game theory, they now need to play a non“zero“sum game where what benefits one benefits others. Those non“zero“sum solutions that best benefit the group will then be selected since they lead to the survival and flourishing of the group. Such solutions include novel biological structures and technological innovation. Accor ding to Wright this is how novel genes and memes are generated.

Let us call this interplay between Darwinian selection, zero“sum games, and non“zero“sum games Wright’s “nonzero dynamic.” According to Wright, the nonzero dynamic confers a direction on biological and cultural evolution by leading to increased complexity over time”the teleology in Wright’s scheme.

To see how complexity emerges from Wright’s nonzero dynamic, consider his favorite metaphor to describe the nonzero dynamic: an “arms race.” An arms race is a zero“sum game between two (or more) nations that leads to a non“zero“sum game within a nation as it desperately seeks to produce the most effective countermeasures against its common enemy. For Wright all biological and cultural progress consists in innovating successful countermeasures according to the nonzero dynamic.

Let’s look at one example of this dynamism at work in biology. Bombardier beetles squirt a hot noxious fluid at predators, a trick that evolved under pressure from predators who would otherwise devour them. But what about the predators who can now no longer devour these beetles and whose livelihood is now in jeopardy? In some cases they evolved novel behaviors for causing the beetle to discharge its fluid harmlessly and thus render it vulnerable. The next round in the arms race may feature an adaptation that improves the beetle’s hot“noxious“fluid delivery system.

This example concerns biological evolution, but according to Wright his nonzero dynamic applies equally well to cultural evolution. Everything from political systems to religious ideas to technological advances is explained by the nonzero dynamic. One political system gives way to another because it cannot handle new challenges. One religion gives way to another because it can no longer make sense of the world. One technology gives way to another because it can no longer keep pace with our needs. According to Wright, the nonzero dynamic drives innovation and thereby continually enriches and regenerates the world.

Wright sees the nonzero dynamic as a positive force in history. In purchasing increased complexity over time, biological and cultural evolution also purchases increasingly complex networks of what Wright calls “non“zero“sumness.” (For Wright this word, more than any other, captures what his book is about”he even wanted to make it the title, though prudence, and editors with an ear for the English language, ultimately dissuaded him.) Complex innovations require complex organizational structures to produce them. Thus, according to Wright, the nonzero dynamic leads inexorably to increasingly larger webs of interconnectedness, of which the World Wide Web is currently our most notable example. Moreover, once a web of interconnectedness playing a non“zero“sum game becomes global, some degree of universal cooperation is achieved.

But Wright is not a utopian. Although the push of the nonzero dynamic is toward increased cooperation, historical contingency can always derail non“zero“sumness in any given instance. The nonzero dynamic is probabilistic and statistical; it says where history as a whole is heading without guaranteeing where any item of history may end up. According to Wright, humans may well destroy themselves in a nuclear holocaust. But if so, a new species will take its place, one that attains our level of intelligence but is more adept at enabling universal non“zero“sumness to prevail. The message of Wright’s book is, to paraphrase John Lennon, “give non“zero“sumness a chance.”

Here, then, is Wright’s grand vision. What can be said about it by way of criticism? Perhaps the most well“known criticism comes from Stephen Jay Gould, who in works that predate Wright’s argues that biological and cultural evolution is thoroughly contingent”that if the tape of history were replayed, not only would we not be here, but nothing like us would be here. Nonetheless, the pattern of convergence in biological and cultural evolution seriously undermines Gould’s contingency claim. The same sorts of biological structures and cultural artifacts keep being reinvented. Eyes have been reinvented dozens of times in the course of evolutionary history. And how many times has the wheel been invented in human history?

A different line of criticism begins with what philosopher David Lewis calls an “incredulous stare.” Whatever the arguments pro or con, it is simply too much to believe that the nonzero dynamic can explain the totality of biological and cultural evolution. Wright’s nonzero dynamic is a universal problem“solver that purports to explain everything and thus explains too much. The skeptic in us shies away from such universal problem“solvers.

Even so, an incredulous stare is not an argument. What specifically is wrong with Wright’s nonzero dynamic? In a recent debate at Baylor University between Wright and professional skeptic Michael Shermer, Shermer tried to run through some examples from biological and cultural evolution where the nonzero dynamic failed. The problem is that the nonzero dynamic is incredibly plastic. Indeed, by being fundamentally probabilistic, it is able to accommodate apparent exceptions by dismissing them as failed experiments that do nothing to undermine the ultimate success of non“zero“sumness.

Although there is a flaw in the nonzero dynamic, it can’t be shown through historical counterexamples. The subtitle of Wright’s book is, after all, “The Logic of Human Destiny,” and it is here that the weakness in his argument appears”though perhaps the problem is not so much logical error as oversight. Wright is on to something with his nonzero dynamic, but it is not the complete explanation of natural and historical development he takes it to be. Wright argues that the nonzero dynamic is sufficient to account for biological and cultural innovation. I would argue that it forms a necessary backdrop for biological and cultural innovation, but that besides Darwinian natural selection and game theory a tertium quid is required”namely, intelligence.

The indispensability of this tertium quid becomes evident when we compare Wright’s treatment of cultural evolution to his treatment of biological evolution. Although the nonzero dynamic is supposed to assimilate both to a common framework, Wright’s treatment of the two is actually quite different. Over and over we read that a non“zero“sum situation leads to some cultural innovation because it was a “good idea.” But good ideas only come from idea“makers, namely, intelligent agents. Non zero dynamics set the stage for innovations to occur, but they are not sufficient. A telephone may be a good idea given a certain stage in cultural evolution, but it still takes an Alexander Graham Bell to invent it. This is obvious for cultural changes, but Wright overlooks the fact that biological innovations also require intelligent agents to actualize the conditions made possible by the nonzero dynamic. A bacterial flagellum may be a good idea for propelling bacteria through watery environments, but who or what is the designer of such bi-directional outboard rotary motors?

Wright would have us believe that any addition of intelligent agency to his nonzero dynamic is superfluous. For Wright, natural selection is an incredibly creative force that produced the very human intellects that in turn guide cultural evolution. The “good ideas” needed to make biological and cultural evolution work are, for Wright, ultimately explained by natural selection. If natural selection is not the creative force that he makes out, though, then Wright’s argument is in trouble. He assumes without argument the strongest claims on behalf of Darwinism and from there develops his nonzero dynamic. But the capacity of the Darwinian mechanism to generate complex, information“rich biological structures is increasingly coming under fire, and not just from members of the burgeoning intelligent design movement. Complex self“organization, as developed by the Santa Fe Institute, a scientific think tank, is also challenging the completeness of Darwinian natural selection as a mechanism for generating biological innovation. Complex systems, according to the Santa Fe paradigm, can emerge from purely physical properties of an underlying physical substrate”e.g., hexagonal frost patterns emerge spontaneously by water condensing on a cold window pane.

To sum up, this is an intelligent and well“written book that should be read by anyone interested in whether history has a direction. It is an ambitious book, and somewhat predictably tries to do too much, assimilating the grand sweep of history to an ultimately inadequate framework. In particular, by placing inordinate weight on natural selection, Wright fails to address adequately the challenge posed by intelligent agency. Indeed, it is becoming increasingly implausible that all the good ideas in history ultimately derive from natural selection”non“zero“sumness notwithstanding.

William A. Dembski is a fellow of the Center for the Renewal of Science and Culture at the Seattle“based Discovery Institute. His latest book is Intelligent Design: The Bridge Between Science and Theology.

Continue Reading »

Are We Spiritual Machines?

Fri, 01 Oct 1999 00:00:00 -0400

Continue Reading »

Science and Design

Thu, 01 Oct 1998 00:00:00 -0400

When the physics of Galileo and Newton displaced the physics of Aristotle, scientists tried to explain the world by discovering its deterministic natural laws. When the quantum physics of Bohr and Heisenberg in turn displaced the physics of Galileo and Newton, scientists realized they needed to supplement their deterministic natural laws by taking into account chance processes in their explanations of our universe. Chance and necessity, to use a phrase made famous by Jacques Monod, thus set the boundaries of scientific explanation.

Today, however, chance and necessity have proven insufficient to account for all scientific phenomena. Without invoking the rightly discarded teleologies, entelechies, and vitalisms of the past, one can still see that a third mode of explanation is required, namely, intelligent design. Chance, necessity, and design”these three modes of explanation”are needed to explain the full range of scientific phenomena.

Not all scientists see that excluding intelligent design artificially restricts science, however. Richard Dawkins, an arch-Darwinist, begins his book The Blind Watchmaker by stating, “Biology is the study of complicated things that give the appearance of having been designed for a purpose.” Statements like this echo throughout the biological literature. In What Mad Pursuit, Francis Crick, Nobel laureate and codiscoverer of the structure of DNA, writes, “Biologists must constantly keep in mind that what they see was not designed, but rather evolved.”

The biological community thinks it has accounted for the apparent design in nature through the Darwinian mechanism of random mutation and natural selection. The point to appreciate, however, is that in accounting for the apparent design in nature, biologists regard themselves as having made a successful scientific argument against actual design. This is important, because for a claim to be scientifically falsifiable, it must have the possibility of being true. Scientific refutation is a double-edged sword. Claims that are refuted scientifically may be wrong, but they are not necessarily wrong”they cannot simply be dismissed out of hand.

To see this, consider what would happen if microscopic examination revealed that every cell was inscribed with the phrase “Made by Yahweh.” Of course cells don’t have “Made by Yahweh” inscribed on them, but that’s not the point. The point is that we wouldn’t know this unless we actually looked at cells under the microscope. And if they were so inscribed, one would have to entertain the thought, as a scientist, that they actually were made by Yaweh. So even those who do not believe in it tacitly admit that design always remains a live option in biology. A priori prohibitions against design are philosophically unsophisticated and easily countered. Nonetheless, once we admit that design cannot be excluded from science without argument, a weightier question remains: Why should we want to admit design into science?

To answer this question, let us turn it around and ask instead, Why shouldn’t we want to admit design into science? What’s wrong with explaining something as designed by an intelligent agent? Certainly there are many everyday occurrences that we explain by appealing to design. Moreover, in our workaday lives it is absolutely crucial to distinguish accident from design. We demand answers to such questions as, Did she fall or was she pushed? Did someone die accidentally or commit suicide? Was this song conceived independently or was it plagiarized? Did someone just get lucky on the stock market or was there insider trading?

Not only do we demand answers to such questions, but entire industries are devoted to drawing the distinction between accident and design. Here we can include forensic science, intellectual property law, insurance claims investigation, cryptography, and random number generation”to name but a few. Science itself needs to draw this distinction to keep itself honest. Just last January there was a report in Science that a Medline websearch uncovered a “paper published in Zentralblatt für Gynäkologie in 1991 [containing] text that is almost identical to text from a paper published in 1979 in the Journal of Maxillofacial Surgery .” Plagiarism and data falsification are far more common in science than we would like to admit. What keeps these abuses in check is our ability to detect them.

If design is so readily detectable outside science, and if its detectability is one of the key factors keeping scientists honest, why should design be barred from the content of science? Why do Dawkins and Crick feel compelled to constantly remind us that biology studies things that only appear to be designed, but that in fact are not designed? Why couldn’t biology study things that are designed?

The biological community’s response to these questions has been to resist design absolutely. The worry is that for natural objects (unlike human artifacts) the distinction between design and non-design cannot be reliably drawn. Consider, for instance, the following remark by Darwin in the concluding chapter of his Origin of Species : “Several eminent naturalists have of late published their belief that a multitude of reputed species in each genus are not real species; but that other species are real, that is, have been independently created . . . . Nevertheless they do not pretend that they can define, or even conjecture, which are the created forms of life, and which are those produced by secondary laws. They admit variation as a vera causa in one case, they arbitrarily reject it in another, without assigning any distinction in the two cases.” Biologists worry about attributing something to design (here identified with creation) only to have it overturned later; this widespread and legitimate concern has prevented them from using intelligent design as a valid scientific explanation.

Though perhaps justified in the past, this worry is no longer tenable. There now exists a rigorous criterion-complexity-specification-for distinguishing intelligently caused objects from unintelligently caused ones. Many special sciences already use this criterion, though in a pre-theoretic form (e.g., forensic science, artificial intelligence, cryptography, archeology, and the Search for Extra-Terrestrial Intelligence). The great breakthrough in philosophy of science and probability theory of recent years has been to isolate and make precise this criterion. Michael Behe’s criterion of irreducible complexity for establishing the design of biochemical systems is a special case of the complexity-specification criterion for detecting design (cf. Behe’s book Darwin’s Black Box ).

What does this criterion look like? Although a detailed explanation and justification is fairly technical (for a full account see my book The Design Inference , published by Cambridge University Press), the basic idea is straightforward and easily illustrated. Consider how the radio astronomers in the movie Contact detected an extraterrestrial intelligence. This movie, which came out last year and was based on a novel by Carl Sagan, was an enjoyable piece of propaganda for the SETI research program”the Search for Extra”Terrestrial Intelligence. In the movie, the SETI researchers found extraterrestrial intelligence. (The nonfictional researchers have not been so successful.)

How, then, did the SETI researchers in Contact find an extraterrestrial intelligence? SETI researchers monitor millions of radio signals from outer space. Many natural objects in space (e.g., pulsars) produce radio waves. Looking for signs of design among all these naturally produced radio signals is like looking for a needle in a haystack. To sift through the haystack, SETI researchers run the signals they monitor through computers programmed with pattern-matchers. As long as a signal doesn’t match one of the pre-set patterns, it will pass through the pattern-matching sieve (even if it has an intelligent source). If, on the other hand, it does match one of these patterns, then, depending on the pattern matched, the SETI researchers may have cause for celebration.

The SETI researchers in Contact found the following signal:

110111011111011111110111111111110111111111111101111111111111111101111111
111111111111011111111111111111111111011111111111111111111111111111011111
111111111111111111111111110111111111111111111111111111111111111101111111
111111111111111111111111111111111101111111111111111111111111111111111111
111111011111111111111111111111111111111111111111111111011111111111111111
111111111111111111111111111111111111011111111111111111111111111111111111
111111111111111111111111110111111111111111111111111111111111111111111111
111111111111111111111101111111111111111111111111111111111111111111111111
111111111111111111111101111111111111111111111111111111111111111111111111
111111111111111111111111011111111111111111111111111111111111111111111111
111111111111111111111111111111110111111111111111111111111111111111111111
111111111111111111111111111111111111111111110111111111111111111111111111
111111111111111111111111111111111111111111111111111111111111110111111111
111111111111111111111111111111111111111111111111111111111111111111111111
111111111111111101111111111111111111111111111111111111111111111111111111
1111111111111111111111111111111111111111111111

In this sequence of 1126 bits, 1’s correspond to beats and 0’s to pauses. This sequence represents the prime numbers from 2 to 101, where a given prime number is represented by the corresponding number of beats (i.e., 1’s), and the individual prime numbers are separated by pauses (i.e., 0’s).

The SETI researchers in Contact took this signal as decisive confirmation of an extraterrestrial intelligence. What is it about this signal that decisively indicates design? Whenever we infer design, we must establish two things”complexity and specification. Complexity ensures that the object in question is not so simple that it can readily be explained by chance. Specification ensures that this object exhibits the type of pattern that is the trademark of intelligence.

To see why complexity is crucial for inferring design, consider the following sequence of bits:

110111011111

These are the first twelve bits in the previous sequence representing the prime numbers 2, 3, and 5 respectively. Now it is a sure bet that no SETI researcher, if confronted with this twelve-bit sequence, is going to contact the science editor at the New York Times , hold a press conference, and announce that an extraterrestrial intelligence has been discovered. No headline is going to read, “Aliens Master First Three Prime Numbers!”

The problem is that this sequence is much too short (i.e., has too little complexity) to establish that an extraterrestrial intelligence with knowledge of prime numbers produced it. A randomly beating radio source might by chance just happen to put out the sequence “110111011111.” A sequence of 1126 bits representing the prime numbers from 2 to 101, however, is a different story. Here the sequence is sufficiently long (i.e., has enough complexity) to confirm that an extraterrestrial intelligence could have produced it.

Even so, complexity by itself isn’t enough to eliminate chance and indicate design. If I flip a coin 1,000 times, I’ll participate in a highly complex (or what amounts to the same thing, highly improbable) event. Indeed, the sequence I end up flipping will be one in a trillion trillion trillion . . . , where the ellipsis needs twenty-two more “trillions.” This sequence of coin tosses won’t, however, trigger a design inference. Though complex, this sequence won’t exhibit a suitable pattern. Contrast this with the sequence representing the prime numbers from 2 to 101. Not only is this sequence complex, it also embodies a suitable pattern. The SETI researcher who in the movie Contact discovered this sequence put it this way: “This isn’t noise, this has structure.”

What is a suitable pattern for inferring design? Not just any pattern will do. Some patterns can legitimately be employed to infer design whereas others cannot. It is easy to see the basic intuition here. Suppose an archer stands fifty meters from a large wall with bow and arrow in hand. The wall, let’s say, is sufficiently large that the archer can’t help but hit it. Now suppose each time the archer shoots an arrow at the wall, the archer paints a target around the arrow so that the arrow sits squarely in the bull’s-eye. What can be concluded from this scenario? Absolutely nothing about the archer’s ability as an archer. Yes, a pattern is being matched; but it is a pattern fixed only after the arrow has been shot. The pattern is thus purely ad hoc.

But suppose instead the archer paints a fixed target on the wall and then shoots at it. Suppose the archer shoots a hundred arrows, and each time hits a perfect bull’s-eye. What can be concluded from this second scenario? Confronted with this second scenario we are obligated to infer that here is a world-class archer, one whose shots cannot legitimately be explained by luck, but rather must be explained by the archer’s skill and mastery. Skill and mastery are of course instances of design.

Like the archer who fixes the target first and then shoots at it, statisticians set what is known as a rejection region prior to an experiment. If the outcome of an experiment falls within a rejection region, the statistician rejects the hypothesis that the outcome is due to chance. The pattern doesn’t need to be given prior to an event to imply design. Consider the following cipher text:

nfuijolt ju jt mjlf b xfbtfm

Initially this looks like a random sequence of letters and spaces”initially you lack any pattern for rejecting chance and inferring design.

But suppose next that someone comes along and tells you to treat this sequence as a Caesar cipher, moving each letter one notch down the alphabet. Behold, the sequence now reads,

methinks it is like a weasel

Even though the pattern is now given after the fact, it still is the right sort of pattern for eliminating chance and inferring design. In contrast to statistics, which always tries to identify its patterns before an experiment is performed, cryptanalysis must discover its patterns after the fact. In both instances, however, the patterns are suitable for inferring design.

Patterns divide into two types, those that in the presence of complexity warrant a design inference and those that despite the presence of complexity do not warrant a design inference. The first type of pattern is called a specification , the second a fabrication . Specifications are the non-ad hoc patterns that can legitimately be used to eliminate chance and warrant a design inference. In contrast, fabrications are the ad hoc patterns that cannot legitimately be used to warrant a design inference. This distinction between specifications and fabrications can be made with full statistical rigor (cf. The Design Inference ).

Why does the complexity”specification criterion reliably detect design? To answer this, we need to understand what it is about intelligent agents that makes them detectable in the first place. The principal characteristic of intelligent agency is choice. Whenever an intelligent agent acts, it chooses from a range of competing possibilities.

This is true not just of humans and extraterrestrial intelligences, but of animals as well. A rat navigating a maze must choose whether to go right or left at various points in the maze. When SETI researchers attempt to discover intelligence in the radio transmissions they are monitoring, they assume an extraterrestrial intelligence could have chosen to transmit any number of possible patterns, and then attempt to match the transmissions they observe with the patterns they seek. Whenever a human being utters meaningful speech, he chooses from a range of utterable sound-combinations. Intelligent agency always entails discrimination”choosing certain things, ruling out others.

Given this characterization of intelligent agency, how do we recognize that an intelligent agent has made a choice? A bottle of ink spills accidentally onto a sheet of paper; someone takes a fountain pen and writes a message on a sheet of paper. In both instances ink is applied to paper. In both instances one among an almost infinite set of possibilities is realized. In both instances one contingency is actualized and others are ruled out. Yet in one instance we ascribe agency, in the other chance.

What is the relevant difference? Not only do we need to observe that a contingency was actualized, but we ourselves need also to be able to specify that contingency. The contingency must conform to an independently given pattern, and we must be able independently to formulate that pattern. A random ink blot is unspecifiable; a message written with ink on paper is specifiable. Wittgenstein in Culture and Value made the same point: “We tend to take the speech of a Chinese for inarticulate gurgling. Someone who understands Chinese will recognize language in what he hears.”

In hearing a Chinese utterance, someone who understands Chinese not only recognizes that one from a range of all possible utterances was actualized, but he is also able to identify the utterance as coherent Chinese speech. Contrast this with someone who does not understand Chinese. He will also recognize that one from a range of possible utterances was actualized, but this time, because he lacks the ability to understand Chinese, he is unable to tell whether the utterance was coherent speech.

To someone who does not understand Chinese, the utterance will appear gibberish. Gibberish”the utterance of nonsense syllables uninterpretable within any natural language”always actualizes one utterance from the range of possible utterances. Nevertheless, gibberish, by corresponding to nothing we can understand in any language, also cannot be specified. As a result, gibberish is never taken for intelligent communication, but always for what Wittgenstein calls “inarticulate gurgling.”

Experimental psychologists who study animal learning and behavior employ a similar method. To learn a task an animal must acquire the ability to actualize behaviors suitable for the task as well as the ability to rule out behaviors unsuitable for the task. Moreover, for a psychologist to recognize that an animal has learned a task, it is necessary not only to observe the animal making the appropriate discrimination, but also to specify this discrimination.

Thus to recognize whether a rat has successfully learned how to traverse a maze, a psychologist must first specify which sequence of right and left turns conducts the rat out of the maze. No doubt, a rat randomly wandering a maze also discriminates a sequence of right and left turns. But by randomly wandering the maze, the rat gives no indication that it can discriminate the appropriate sequence of right and left turns for exiting the maze. Consequently, the psychologist studying the rat will have no reason to think the rat has learned how to traverse the maze. Only if the rat executes the sequence of right and left turns specified by the psychologist will the psychologist recognize that the rat has learned how to traverse the maze.

Note that complexity is implicit here as well. To see this, consider again a rat traversing a maze, but now take a very simple maze in which two right turns conduct the rat out of the maze. How will a psychologist studying the rat determine whether it has learned to exit the maze? Just putting the rat in the maze will not be enough. Because the maze is so simple, the rat could by chance just happen to take two right turns, and thereby exit the maze. The psychologist will therefore be uncertain whether the rat actually learned to exit this maze, or whether the rat just got lucky.

But contrast this now with a complicated maze in which a rat must take just the right sequence of left and right turns to exit the maze. Suppose the rat must take one hundred appropriate right and left turns, and that any mistake will prevent the rat from exiting the maze. A psychologist who sees the rat take no erroneous turns and in short order exit the maze will be convinced that the rat has indeed learned how to exit the maze, and that this was not dumb luck.

This general scheme for recognizing intelligent agency is but a thinly disguised form of the complexity-specification criterion. In general, to recognize intelligent agency we must observe a choice among competing possibilities, note which possibilities were not chosen, and then be able to specify the possibility that was chosen. What’s more, the competing possibilities that were ruled out must be live possibilities, and sufficiently numerous (hence complex) so that specifying the possibility that was chosen cannot be attributed to chance.

All the elements in this general scheme for recognizing intelligent agency (i.e., choosing, ruling out, and specifying) find their counterpart in the complexity-specification criterion. It follows that this criterion formalizes what we have been doing right along when we recognize intelligent agency. The complexity-specification criterion pinpoints what we need to be looking for when we detect design.

Perhaps the most compelling evidence for design in biology comes from biochemistry. In a recent issue of Cell (February 8, 1998), Bruce Alberts, president of the National Academy of Sciences, remarked, “The entire cell can be viewed as a factory that contains an elaborate network of interlocking assembly lines, each of which is composed of large protein machines . . . . Why do we call the large protein assemblies that underlie cell function machines ? Precisely because, like the machines invented by humans to deal efficiently with the macroscopic world, these protein assemblies contain highly coordinated moving parts.”

Even so, Alberts sides with the majority of biologists in regarding the cell’s marvelous complexity as only apparently designed. The Lehigh University biochemist Michael Behe disagrees. In Darwin’s Black Box (1996), Behe presents a powerful argument for actual design in the cell. Central to his argument is his notion of irreducible complexity . A system is irreducibly complex if it consists of several interrelated parts so that removing even one part completely destroys the system’s function. As an example of irreducible complexity Behe offers the standard mousetrap. A mousetrap consists of a platform, a hammer, a spring, a catch, and a holding bar. Remove any one of these five components, and it is impossible to construct a functional mousetrap.

Irreducible complexity needs to be contrasted with cumulative complexity . A system is cumulatively complex if the components of the system can be arranged sequentially so that the successive removal of components never leads to the complete loss of function. An example of a cumulatively complex system is a city. It is possible successively to remove people and services from a city until one is down to a tiny village”all without losing the sense of community, the city’s “function.”

From this characterization of cumulative complexity, it is clear that the Darwinian mechanism of natural selection and random mutation can readily account for cumulative complexity. Darwin’s account of how organisms gradually become more complex as favorable adaptations accumulate is the flip side of the city in our example from which people and services are removed. In both cases, the simpler and more complex versions both work, only less or more effectively.

But can the Darwinian mechanism account for irreducible complexity? Certainly, if selection acts with reference to a goal, it can produce irreducible complexity. Take Behe’s mousetrap. Given the goal of constructing a mousetrap, one can specify a goal-directed selection process that in turn selects a platform, a hammer, a spring, a catch, and a holding bar, and at the end puts all these components together to form a functional mousetrap. Given a pre-specified goal, selection has no difficulty producing irreducibly complex systems.

But the selection operating in biology is Darwinian natural selection. And by definition this form of selection operates without goals, has neither plan nor purpose, and is wholly undirected. The great appeal of Darwin’s selection mechanism was, after all, that it would eliminate teleology from biology. Yet by making selection an undirected process, Darwin drastically reduced the type of complexity biological systems could manifest. Henceforth biological systems could manifest only cumulative complexity, not irreducible complexity.

As Behe explains in Darwin’s Black Box , “An irreducibly complex system cannot be produced . . . by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional . . . . Since natural selection can only choose systems that are already working, then if a bio logical system cannot be produced gradually it would have to arise as an integrated unit, in one fell swoop, for natural selection to have anything to act on.”

For an irreducibly complex system, function is attained only when all components of the system are in place simultaneously. It follows that natural selection, if it is going to produce an irreducibly complex system, has to produce it all at once or not at all. This would not be a problem if the systems in question were simple. But they’re not. The irreducibly complex biochemical systems Behe considers are protein machines consisting of numerous distinct proteins, each indispensable for function; together they are beyond what natural selection can muster in a single generation.

One such irreducibly complex biochemical system that Behe considers is the bacterial flagellum. The flagellum is a whip-like rotary motor that enables a bacterium to navigate through its environment. The flagellum includes an acid-powered rotary engine, a stator, O-rings, bushings, and a drive shaft. The intricate machinery of this molecular motor requires approximately fifty proteins. Yet the absence of any one of these proteins results in the complete loss of motor function.

The irreducible complexity of such biochemical systems cannot be explained by the Darwinian mechanism, nor indeed by any naturalistic evolutionary mechanism proposed to date. Moreover, because irreducible complexity occurs at the biochemical level, there is no more fundamental level of biological analysis to which the irreducible complexity of biochemical systems can be referred, and at which a Darwinian analysis in terms of selection and mutation can still hope for success. Undergirding biochemistry is ordinary chemistry and physics, neither of which can account for biological information. Also, whether a biochemical system is irreducibly complex is a fully empirical question: Individually knock out each protein constituting a biochemical system to determine whether function is lost. If so, we are dealing with an irreducibly complex system. Experiments of this sort are routine in biology.

The connection between Behe’s notion of irreducible complexity and my complexity-specification criterion is now straightforward. The irreducibly complex systems Behe considers require numerous components specifically adapted to each other and each necessary for function. That means they are complex in the sense required by the complexity-specification criterion.

Specification in biology always makes reference in some way to an organism’s function. An organism is a functional system comprising many functional subsystems. The functionality of organisms can be specified in any number of ways. Arno Wouters does so in terms of the viability of whole organisms, Michael Behe in terms of the minimal function of biochemical systems. Even Richard Dawkins will admit that life is specified functionally, for him in terms of the reproduction of genes. Thus in The Blind Watchmaker Dawkins writes, “Complicated things have some quality, specifiable in advance, that is highly unlikely to have been acquired by random chance alone. In the case of living things, the quality that is specified in advance is . . . the ability to propagate genes in reproduction.”

So there exists a reliable criterion for detecting design strictly from observational features of the world. This criterion belongs to probability and complexity theory, not to metaphysics and theology. And although it cannot achieve logical demonstration, it does achieve a statistical justification so compelling as to demand assent. This criterion is relevant to biology. When applied to the complex, information-rich structures of biology, it detects design. In particular, we can say with the weight of science behind us that the complexity-specification criterion shows Michael Behe’s irreducibly complex biochemical systems to be designed.

What are we to make of these developments? Many scientists remain unconvinced. Even if we have a reliable criterion for detecting design, and even if that criterion tells us that biological systems are designed, it seems that determining a biological system to be designed is akin to shrugging our shoulders and saying God did it. The fear is that admitting design as an explanation will stifle scientific inquiry, that scientists will stop investigating difficult problems because they have a sufficient explanation already.

But design is not a science stopper. Indeed, design can foster inquiry where traditional evolutionary approaches obstruct it. Consider the term “junk DNA.” Implicit in this term is the view that because the genome of an organism has been cobbled together through a long, undirected evolutionary process, the genome is a patchwork of which only limited portions are essential to the organism. Thus on an evolutionary view we expect a lot of useless DNA. If, on the other hand, organisms are designed, we expect DNA, as much as possible, to exhibit function. And indeed, the most recent findings suggest that designating DNA as “junk” merely cloaks our current lack of knowledge about function. For instance, in a recent issue of the Journal of Theoretical Biology , John Bodnar describes how “non-coding DNA in eukaryotic genomes encodes a language which programs organismal growth and development.” Design encourages scientists to look for function where evolution discourages it.

Or consider vestigial organs that later are found to have a function after all. Evolutionary biology texts often cite the human coccyx as a “vestigial structure” that hearkens back to vertebrate ancestors with tails. Yet if one looks at a recent edition of Gray’s Anatomy , one finds that the coccyx is a crucial point of contact with muscles that attach to the pelvic floor. The phrase “vestigial structure” often merely cloaks our current lack of knowledge about function. The human appendix, formerly thought to be vestigial, is now known to be a functioning component of the immune system.

Admitting design into science can only enrich the scientific enterprise. All the tried and true tools of science will remain intact. But design adds a new tool to the scientist’s explanatory tool chest. Moreover, design raises a whole new set of research questions. Once we know that something is designed, we will want to know how it was produced, to what extent the design is optimal, and what is its purpose. Note that we can detect design without knowing what something was designed for. There is a room at the Smithsonian filled with objects that are obviously designed but whose specific purpose anthropologists do not understand.

Design also implies constraints. An object that is designed functions within certain constraints. Transgress those constraints and the object functions poorly or breaks. Moreover, we can discover those constraints empirically by seeing what does and doesn’t work. This simple insight has tremendous implications not just for science but also for ethics. If humans are in fact designed, then we can expect psychosocial constraints to be hardwired into us. Transgress those constraints, and we as well as our society will suffer. There is plenty of empirical evidence to suggest that many of the attitudes and behaviors our society promotes undermine human flourishing. Design promises to reinvigorate that ethical stream running from Aristotle through Aquinas known as natural law.

By admitting design into science, we do much more than simply critique scientific reductionism. Scientific reductionism holds that everything is reducible to scientific categories. Scientific reductionism is self-refuting and easily seen to be self-refuting. The existence of the world, the laws by which the world operates, the intelligibility of the world, and the unreasonable effectiveness of mathematics for comprehending the world are just a few of the questions that science raises, but that science is incapable of answering.

Simply critiquing scientific reductionism, however, is not enough. Critiquing reductionism does nothing to change science. And it is science that must change. By eschewing design, science has for too long operated with an inadequate set of conceptual categories. This has led to a constricted vision of reality, skewing how science understands not just the world, but also human beings.

Martin Heidegger remarked in Being and Time that “a science’s level of development is determined by the extent to which it is capable of a crisis in its basic concepts.” The basic concepts with which science has operated these last several hundred years are no longer adequate, certainly not in an information age, certainly not in an age where design is empirically detectable. Science faces a crisis of basic concepts. The way out of this crisis is to expand science to include design. To admit design into science is to liberate science, freeing it from restrictions that can no longer be justified.

Continue Reading »

The Bible by Numbers

Sat, 01 Aug 1998 00:00:00 -0400

Cracking the Bible Code
By Jeffrey Satinover
Morrow. 346 pp. $23

Continue Reading »