Reprinted with permission of Free Inquiry magazine.

As a Darwinian, the aspect of religion that catches my attention is its profligate wastefulness, its extravagant display of baroque uselessness. Nature is a miserly accountant, grudging the pennies, watching the clock, punishing the smallest waste. If a wild animal habitually performs some useless activity, natural selection will favor rival individuals who instead devote time to surviving and reproducing. Nature cannot afford frivolous jeux d'esprit. Ruthless utilitarianism trumps, even if it doesn't always seem that way. "Anting" is the odd habit of birds such as jays of "bathing" in an ants' nest and apparently inciting the ants to invade their feathers. Nobody knows for sure what the benefit of anting is: perhaps some kind of hygiene, cleansing the feathers of parasites. My point is that uncertainty as to the purpose doesn't-nor should it-stop Darwinians from believing, with great confidence, that anting must be good for something. Religious behavior in bipedal apes occupies large quantities of time. It devours huge resources. A medieval cathedral consumed hundreds of man-centuries in its building. Sacred music and devotional paintings largely monopolized medieval and Renaissance talent. Thousands, perhaps millions, of people have died, often accepting torture first, for loyalty to one religion against a scarcely distinguishable alternative. Devout people have died for their gods, killed for them, fasted for them, endured whipping, undertaken a lifetime of celibacy, and sworn themselves to asocial silence for the sake of religion. Though the details differ across cultures, no known culture lacks some version of the time-consuming, wealth-consuming, hostility-provoking, fecundity-forfeiting rituals of religion. All this presents a major puzzle to anyone who thinks in a Darwinian way. We guessed why jays ant. Isn't religion a similar challenge, an a priori affront to Darwinism, demanding analogous explanation? Why do we pray and indulge in costly practices that, in many individual cases, more or less totally consume lives? Of course, the caveats must now come tumbling in. Religious behavior is Darwinian business only if it is widespread, not some weird anomaly. Apparently, it is universal, and the problem won't go away just because the details differ across cultures. As with language, the underlying phenomenon is universal, though it plays out differently in different regions. Not all individuals are religious, as most readers of this journal can testify. But religion is a human universal: every culture, everywhere in the world, has a style of religion that even nonpractitioners recognize as the norm for that society, just as it has a style of clothing, a style of courting, and a style of meal serving. What is religion good for? There is a little evidence that religious belief protects people from stress-related diseases. The evidence is not good, but it would not be at all surprising. A non-negligible part of what a doctor can provide for a patient is consolation and reassurance. My doctor doesn't literally practice the laying on of hands. But many's the time I have been instantly cured of some minor ailment by a reassuringly calm voice from an intelligent face surmounting a stethoscope. The placebo effect is well-documented. Dummy pills, with no pharmacological activity at all, demonstrably improve health. That is why drug trials have to use placebos as controls. It's why homeopathic remedies appear to work, even though they're so diluted that they contain the same amount of the active ingredient as the placebo control-zero molecules. Is religion a medical placebo, which prolongs life by reducing stress? Perhaps, although the theory is going to have to run the gauntlet of skeptics who point out the many circumstances in which religion increases stress rather than decreases it. In any case, I find the placebo theory too meager to account for the massive and all-pervasive phenomenon of religion. I do not think we have religion because our religious ancestors reduced their stress levels and hence survived longer. I don't think that's a big enough theory for the job. Other theories miss the point of Darwinian explanations altogether. I refer to suggestions like, "Religion satisfies our curiosity about the universe and our place in it." Or "Religion is consoling. People fear death and are drawn to religions which promise we'll survive it." There may be some psychological truth here, but it's not in itself a Darwinian explanation. As Steven Pinker has said in How the Mind Works (Penguin, 1997):

...it only raises the question of why a mind would evolve to find comfort in beliefs it can plainly see are false. A freezing person finds no comfort in believing he is warm; a person face-to-face with a lion is not put at ease by the conviction that it is a rabbit.

A Darwinian version of the fear-of-death theory would have to be of the form, "Belief in survival after death tends to postpone the moment when it is put to the test." This could be true or it could be false-maybe it's another version of the stress and placebo theory-but I shall not pursue the matter. My only point is that this is the kind of way in which a Darwinian must rewrite the question. Psychological statements to the effect that people find some belief agreeable or disagreeable are proximate, not ultimate explanations. As a Darwinian, I am concerned with ultimate questions. Darwinians make much of this distinction between proximate and ultimate. Proximate questions lead us into physiology and neuroanatomy. There is nothing wrong with proximate explanations. They are important, and they are scientific. But my pre-occupation is with Darwinian ultimate explanations. If neuroscientists find a "god center" in the brain, Darwinian scientists like me want to know why the god center evolved. Why did those of our ancestors who had a genetic tendency to grow a god center survive better than rivals who did not? The ultimate Darwinian question is not a better question, not a more profound question, not a more scientific question than the proximate neurological question. But it is the one I happen to be talking about here.

Some alleged ultimate explanations turn out to be--or even avowedly are--group-selection theories. Group selection is the controversial idea that Darwinian selection chooses among groups of individuals, in the same kind of way as, in accordance with normal Darwinian theory, it chooses among individuals within groups. The Cambridge anthropologist Colin Renfrew, for example, suggests that Christianity survived by a form of group-selection because it fostered the idea of in-group loyalty and brotherly love. The American evolutionist David Sloan Wilson has made a similar suggestion in Darwin's Cathedral.

Here's a made-up example, to show another way in which a group-selection theory of religion might work. A tribe with a stirringly belligerent "god of battles" wins wars against a tribe whose god urges peace and harmony or a tribe with no god at all. Warriors who believe a martyr's death will send them straight to paradise fight bravely, and willingly give up their lives. So their tribe is more likely to survive in intertribal selection, steal the conquered tribe's cattle, and seize their women as concubines. Such successful tribes spawn daughter tribes that go off and propagate more daughter tribes, all worshipping the same tribal god. Notice that this is different from saying that the idea of the warlike religion survives. Of course it will, but in this case the point is that the group of people who hold the idea survive. There are formidable objections to group-selection theories. A known opponent, I must beware of riding off on a hobby horse far from this column's subject. Mathematical models arguably come up with very special conditions under which group selection might work. Arguably, religions in human tribes set up just such special conditions. This is an interesting line of theory to pursue, but I shall not do so here. Could religion be a recent phenomenon, sprung up since our genes underwent most of their natural selection? Its ubiquity argues against any simple version of this idea. Nevertheless, there is a version of it that I want to advocate. The propensity that was naturally selected in our ancestors was not religion per se. It had some other benefit, and it only incidentally manifests itself today as religious behavior. We'll understand religious behavior only after we have renamed it. It is natural for me as a zoologist to use an analogy from nonhuman animals. The "dominance hierarchy" was first discovered as the "pecking order" in hens. Each hen learns which individuals she can beat in a fight and which will beat her. In a well-established dominance hierarchy, little overt fighting is seen. Stable groupings of hens, who have had time to sort themselves into a pecking order, lay more eggs than coops whose membership is continually changed. This might suggest an "advantage" to the phenomenon of the dominance hierarchy. But that's not good Darwinism, because the dominance hierarchy is a group-level phenomenon. Farmers may care about group productivity, but, except under very peculiar conditions that don't apply here, natural selection doesn't. For a Darwinian, the question "What is the survival value of the dominance hierarchy?" is illegitimate. The proper question is, "What is the individual survival value of deferring to stronger hens? And of punishing lack of deference from weaker ones?" Darwinian questions have to direct attention toward the level at which genetic variations might exist. Aggressive or deferring tendencies in individual hens are a proper target because they either do, or easily might, vary genetically. Group phenomena like dominance hierarchies don't in themselves vary genetically, because groups don't have genes. Or at least, you'll have your work cut out arguing some peculiar sense in which a group phenomenon could be subject to genetic variation. My point, of course, is that religion may be like the dominance hierarchy. "What is the survival value of religion?" may be the wrong question. The right question may have the form, "What is the survival value of some as yet unspecified individual behavior, or psychological characteristic, that manifests itself, under appropriate circumstances, as religion?" We have to rewrite the question before we can sensibly answer it. Darwinians who seek the survival value of religion are asking the wrong question. Instead, we should focus on something in our evolving ancestors that we would not then have recognized as religion, but which is primed to become recognizable as religion in the changed context of civilized society. I cited the pecking order in hens, and the point is so central to my thesis that I hope you will forgive another animal example to ram it home. Moths fly into the candle flame, and it doesn't look like an accident. They go out of their way to make a burnt offering of themselves. We could label it "self-immolation behavior" and wonder how Darwinian natural selection could possibly favor it. My point, again, is that we need to rewrite the question before we can even attempt an intelligent answer. It isn't suicide. Apparent suicide emerges as an inadvertent side-effect. Artificial light is a recent arrival on the night scene. Until recently, the only night lights were the moon and the stars. Being at optical infinity, their rays are parallel, which makes them ideal compasses. Insects are known to use celestial objects to steer accurately in a straight line. The insect nervous system is adept at setting up a temporary rule of thumb such as, "Steer a course such that the light rays hit your eye at an angle of 30°." Since insects have compound eyes, this will amount to favoring a particular ommatidium (individual optical tube radiating out from the center of the compound eye).

But the light compass relies critically on the celestial object being at optical infinity. If it isn't, the rays are not parallel but diverge like the spokes of a wheel. A nervous system using a 30° rule of thumb to a candle, as though it were the moon, will steer its moth, in a neat logarithmic spiral, into the flame.

It is still, on average, a good rule of thumb. We don't notice the hundreds of moths who are silently and effectively steering by the moon or a bright star or even the lights of a distant city. We see only moths hurling themselves at our lights, and we ask the wrong question. Why are all these moths committing suicide? Instead, we should ask why they have nervous systems that steer by maintaining an automatic fixed angle to light rays, a tactic that we only notice on the occasions when it goes wrong. When the question is rephrased, the mystery evaporates. It never was right to call it suicide. Once again, apply the lesson to religious behavior in humans. We observe large numbers of people-in many local areas it amounts to 100 percent-who hold beliefs that flatly contradict demonstrable scientific facts, as well as rival religions. They not only hold these beliefs but devote time and resources to costly activities that flow from holding them. They die for them, or kill for them. We marvel at all this, just as we marvelled at the self-immolation behavior of the moths. Baffled, we ask "Why?" Yet again, the point I am making is that we may be asking the wrong question. The religious behavior may be a misfiring, an unfortunate manifestation of an underlying psychological propensity that in other circumstances was once useful. What might that psychological propensity have been? What is the equivalent of using the parallel rays from the moon as a useful compass? I shall offer a suggestion, but I must stress that it is only an example of the kind of thing I am talking about. I am much more wedded to the general idea that the question should be properly rephrased than I am to any particular answer. My specific hypothesis is about children. More than any other species, we survive by the accumulated experience of previous generations. Theoretically, children might learn from experience not to swim in crocodile-infested waters. But, to say the least, there will be a selective advantage to child brains with the rule of thumb: Believe whatever your grown-ups tell you. Obey your parents, obey the tribal elders, especially when they adopt a solemn, minatory tone. Obey without question. I have never forgotten a horrifying sermon, preached in my school chapel when I was little. It was horrifying in retrospect: at the time, my child brain accepted it as intended by the preacher. He told the story of a squad of soldiers, drilling beside a railway line. At a critical moment, the drill sergeant's attention was distracted, and he failed to give the order to halt. The soldiers were so well schooled to obey orders without question that they carried on marching, right into the path of an oncoming train. Now, of course, I don't believe the story now, but I did when I was nine. The point is that the preacher wished us children to regard as a virtue the soldiers' slavish and unquestioning obedience to an order, however preposterous. And, speaking for myself, I think we did regard it as a virtue. I wondered whether I would have had the courage to do my duty by marching into the train. Like ideally drilled soldiers, computers do what they are told. They slavishly obey whatever instructions are properly delivered in their own programming language. This is how they do useful things like word processing and spreadsheet calculations. But, as an inevitable by-product, they are equally automatic in obeying bad instructions. They have no way of telling whether an instruction will have a good effect or a bad. They simply obey, as soldiers are supposed to. It is their unquestioning obedience that makes computers vulnerable to infection by viruses and worms. A maliciously designed program that says "Copy me to every name in any address list that you find on this hard disk" will simply be obeyed and then obeyed again by the other computers to which it is sent, in exponential expansion. It is impossible to design a computer that is usefully obedient and at the same time immune to infection. If I have done my softening up work well, you will already have completed the argument about child brains and religion. Natural selection builds child brains with a tendency to believe whatever their parents and tribal elders tell them. And this very quality automatically makes them vulnerable to infection by mind viruses. For excellent survival reasons, child brains need to trust parents and trust elders whom their parents tell them to trust. An automatic consequence is that the "truster" has no way of distinguishing good advice from bad. The child cannot tell that "If you swim in the river you'll be eaten by crocodiles" is good advice but "If you don't sacrifice a goat at the time of the full moon, the crops will fail" is bad advice. They both sound the same. Both are advice from a trusted source, and both are delivered with a solemn earnestness that commands respect and demands obedience. The same goes for propositions about the world, the cosmos, morality, and human nature. And, of course, when the child grows up and has children of his or her own, she will naturally pass the whole lot on to her own children, using the same impressive gravitas of manner. On this model, we should expect that, in different geographical regions, different arbitrary beliefs having no factual basis will be handed down, to be believed with the same conviction as useful pieces of traditional wisdom such as the belief that manure is good for the crops. We should also expect that these nonfactual beliefs will evolve over generations, either by random drift or following some sort of analogue of Darwinian selection, eventually showing a pattern of significant divergence from common ancestry. Languages drift apart from a common parent given sufficient time in geographical separation. The same is true of traditional beliefs and injunctions, handed down the generations, initially because of the programmability of the child brain.

Darwinian selection sets up childhood brains with a tendency to believe their elders. It sets up brains with a tendency to imitate, hence indirectly to spread rumors, spread urban legends, and believe religions. But given that genetic selection has set up brains of this kind, they then provide the equivalent of a new kind of nongenetic heredity, which might form the basis for a new kind of epidemiology, and perhaps even a new kind of nongenetic Darwinian selection. I believe that religion is one of a group of phenomena explained by this kind of nongenetic epidemiology, with the possible admixture of nongenetic Darwinian selection. If I am right, religion has no survival value for individual human beings, nor for the benefit of their genes. The benefit, if there is any, is to religion itself.