Moral reasoning probably evolved because justifying one’s actions to the group would have helped burnish one’s reputation, a matter of the greatest importance for survival in small hunter gatherer bands.
People in a small community gossip all the time and maintain elaborate mental dossiers on one another’s behavior. Any infraction of social norms may be remembered for years. Guarding one’s reputation would have become critical. Hunter gatherer societies don’t run prisons or have a penal code. You’re either in or you’re out, and if you are ostracized your prospects of surviving alone in the wilderness are unpromising. Better learn quickly to fit in and conform.
The fear of disobeying the community’s rules could well have solidified into something close to an imperative. Philosophers looking at the primatologists’ descriptions of primates’ pro-social behaviors like to echo Hume’s remark that there is no way of stepping from “is” to “ought.” But in social situations in which an individual fears community disapproval if he fails to do something, the “is” lies pretty close to the “ought.”
Consider a remarkable human behavior, one seldom hailed as distinguishing people from other animals but quite unique all the same—that of blushing. No other species changes its skin color, against its conscious will, so as to signal to others that it is ashamed or embarrassed. It is hard to reconstruct how blushing evolved. It’s good for the social fabric, so perhaps societies full of blushers were more cohesive and successful. Or maybe individuals who blushed seemed more honest and trustworthy, giving them an advantage.
But however the blushing reflex evolved, it shows how acutely attuned humans have become to the necessity of observing social rules, and to their discomfiture when they feel they have transgressed the bounds of accepted behavior. Morality is at the heart of our social behavior. Evolution seems to have inscribed not just the capacity for learning the moral rules of one’s community, but a significant part of the content.
There may be a universal moral grammar, as Hauser suggests, a counterpart of the universal grammar machinery that enables children to learn the language of their community. But the moral grammar, unlike that for language, is not content free. Many moral rules are universal and therefore likely to have a genetic origin. The anthropologist Donald Brown, in his survey of universal human behaviors found in societies throughout the world, cites reciprocity as the cornerstone of moral values. “The strong moral feeling attached to reciprocity, and the assiduousness with which reciprocal action and reaction are watched also suggest some degree of innateness,” he writes.32
The Universal People, as he calls the exemplars of typical human behavior, display other moral behaviors. They care for children and the helpless. They deplore and punish the following actions: killing, stealing, cheating, lying, breaking promises and committing adultery.33 Causing harm to others is also forbidden, and the three principles uncovered by the trolley problems show how finely grained are the innate moral rules in this category. They distinguish the in-group from the out-group, being more disposed to cooperate with the first.
Moral behavior, on the basis of the findings discussed above, seems very likely to have a genetic basis. The joint ancestors of chimps and humans, who lived some 5 million years ago, were presumably capable of premoral behaviors much like those seen in chimpanzees today. But down the human side of the chimp-human split, individuals were evolving larger brains which eventually reached a volume three times that of chimps.
With the increasing power of the human mind, individuals started to think for themselves and to calculate where their own interests lay. Their assessments of their self-interest often proved to differ from what their moral instincts told them was in the community’s interest. If societies of these cognitively advanced hominids were not to disintegrate, a higher level of social cohesion had to come into play. A new kind of behavior evolved, one that induced individuals to subordinate their own interests to that of the group. This new behavior, the instinct for religion, enforced moral instincts by making people fear deeply the consequences of ignoring them.
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THE EVOLUTION OF RELIGIOUS BEHAVIOR
The human mind evolved to believe in the gods. It did not evolve to believe in biology. Acceptance of the supernatural conveyed a great advantage throughout prehistory, when the brain was evolving. Thus it is in sharp contrast to biology, which was developed as a product of the modern age and is not underwritten by genetic algorithms.
EDWARD O. WILSON34
It is difficult to find a religion which has not, at some stage in its history, inspired in the breasts of at least certain of its followers those transports of mystical exaltation in which man’s whole being seems to fuse in glorious communion with the divinity.
I. M. LEWIS34A
The human form has undergone extraordinary changes since its lineage split from that of chimpanzees some 5 to 6 million years ago. Our brain tripled in size, our body hair was shed, we downsized our teeth, shriveled our gut and gained a fine facial appendage for conserving moisture in dry climates—the nose.
Equally radical and transformative, though less well appreciated, have been the changes in human social behavior. In the societies of our apelike forebears, coordination was achieved relatively simply, through a strict hierarchy dominated by the alpha male. Hunter gatherer societies are organized on a very different principle—they are completely egalitarian. It was during the transition from male dominance to egalitarianism that religious behavior emerged.
Many other social innovations developed in the human lineage as this new species, driven by the increasing intellectual capacity of its individuals, experimented with one novel mechanism after another for communicating among members of a group and governing the interactions among them. The surprising gift of music appeared in the repertoire of human faculties. Even more remarkable was language, a wholly novel system for conveying precise thoughts from one individual’s mind to that of another. Humans developed or enhanced a skill known to psychologists as theory of mind—the ability to infer what someone else knows or intends. Groups possessing these new skills in various strengths competed furiously with each other in the struggle to survive. All these new faculties were doubtless drawn upon as natural selection searched for an effective solution to the most pressing of all problems for a social species—how to make selfish individuals place society’s needs above their own. This departure from self-interest required not just moral self-restraint and social cohesiveness, but an emotional commitment to the group so fierce and transcendent that men would quite readily sacrifice their lives in its defense.
The solution that evolved was religious behavior. It was those who learned to bond to each other through ritual song and dance who developed the most cohesive communities. It was those who believed that the gods or their dead ancestors were seeing into their hearts who hewed closest to their society’s rules. It was those who most feared supernatural retribution who built the most moral societies with the strongest social fabric and the resilience to outlast others.
Common or Universal Features of Religion
The principal evidence for thinking religious behavior is an evolved part of human nature is the fact that religion is universal. Every known society possesses some form of religion. And though there are wide cultural variations—religions across the world are very different from one another—there are also many shared elements. These constant or almost constant features of religious behavior are the ones likely to have a genetic basis.35
All religions are centered on rituals, and the rituals include music. Dance is also a regular part of ritual in primitive societies though it has been eliminated from the religion of many settled societies.
All societies have rites of passage, rituals that mark birth, puberty, marriage and death. The music that accompanies these often includes percussive effects, since drums or rhythmic beating are widely held to be a way of communicating with the spirit world. The initiation rites accompanying puberty often involve
pain and terror, a way of instilling courage and loyalty in future warriors.
All religions include some way of gaining access to the gods, even though the gods live in a different world, and of influencing their behavior through rituals, sacrifice or prayer, even though eternal beings might seem likely to have little interest in quotidian human concerns.
Access to the supernatural realm may be gained through trance in primitive societies, and through revelation in advanced societies. In some primitive societies, anyone may enter the trance state, either through hour-long dancing or by taking hallucinogenic drugs. In others, trance specialists known as shamans venture out on special journeys to the spirit world. In advanced societies, control of religion often rests with a religious hierarchy which monopolizes access to the supernatural. In some religions, access is confined to the occasions in the distant past when the founding prophet received communications from the deity or his surrogates.
In many societies rules of morality are part of the pact with the supernatural powers, an understanding that elevates moral behavior from an individual to a collective matter. Conformance with the gods’ wishes entitles society to their favors. Conversely, if anyone misbehaves and is not punished, the group as a whole stands to suffer divine retribution.
All or almost all religions share the belief that the soul survives after death, and that the gods control both fortunate and unfortunate events.
Even though the gods enjoy eternal lives in their supernatural realm, they are intensely interested in human affairs down to the minutest detail. They are aware of everything and can know a person’s thoughts. They may punish remorselessly every infraction of their rules, with penalties meted out in the form of disease, death or disaster in this world or as sanctions on the soul when it joins the supernatural world.
The divine rules include codes of moral behavior, as well as largely arbitrary ritual requirements, such as taboos on certain foods or on speaking certain words.
The gods can be propitiated with appropriate rituals, which usually include sacrifices of various kinds. The prayers that accompany these propitiatory rituals are accompanied with gestures used in human and other mammalian societies to indicate submission—bared throat or chest, kneeling or prostration.
Central to many religions is the idea of sacrifice, of valuable gifts made to the gods to influence their behavior. As in relationships among people, the gifts impose on the divine recipients the obligation of repayment at a later date. The gods are expected to provide the things people need of them, such as good fortune, good health, good harvests, and victory in war or at least the avoidance of defeat. Sacrifice is a principal means of influencing the gods’ behavior and, along with prayer, of negotiating the expectations between the gods and society as to how each party should behave.
“Beneath the diverse forms it takes,” Henri Hubert and Marcel Mauss wrote in their classic essay, sacrifice “always consists in one same procedure, which may be used for the most widely differing purposes. This procedure consists in establishing a means of communication between the sacred and profane worlds through the mediation of a victim, that is, of a thing that in the course of the ceremony is destroyed.”36 Every sacrifice, in their view, is a contractual arrangement based on the principle of do ut des—“I give that you may give.”
Among the Nuer, for example, a pastoral Nilotic people of the lower Sudan, explicit bargaining negotiations are conducted with the spirits as to how serious a sacrifice is required for their favors. The Nuer spirits, writes the social anthropologist E. E. Evans-Pritchard, “require bloody offerings. And if they are not given animal sacrifices they seize their devotees and make them sick. Nuer, therefore, do not hesitate to bargain with these spirits, speaking through their mediums, in a downright way which astonished me. The sense of the bargain is always the same: if we give you an ox or a sheep or a goat will you leave the sick man alone that he may not be troubled by you?”37
The sacrificed animal is the intermediary between the sacrificer in the living world and the gods in the supernatural world. In some religions the sacrificer sacrifices himself, but this, Hubert and Mauss note, can only happen when the sacrificer is himself a god. In Christianity, the sacrifice has become the death of Jesus, and is performed by the priest metaphorically in the communion rite. Jesus was killed by men of ill will “but by a complex transformation this has retrospectively become a sacrifice, in that the murder was willed by God,” writes the social anthropologist Edmund Leach. “The sacrifice is now a persisting channel through which the grace of God can How to the devout believer. The donor of the sacrifice is Christ himself and the priest, in offering the bread and wine to the congregation as ‘the body and blood of Christ,’ is, by implication, timelessly repeating the sacrifice at the behest of the divine Donor.... The Christian Mass, as a whole, is a transformation of the Jewish Passover and the crucified Christ ‘is’ the sacrificial paschal lamb, ‘the Lamb of God.’ ”38
The remarkable variety of the world’s religions can thus be seen to depend on a handful of common behaviors. Foremost among them is the belief in the gods as awesome governors of society and enforcers of moral standards. Though the gods are known to live in the supernatural realm, people believe that they closely follow events in this world and can be swayed by prayer, sacrifice and appropriate rituals. Societies whose members embraced such beliefs would have been more cohesive and united in attaining difficult goals, whether in peace or warfare. Because an instinct for faith would have promoted survival, genes that favored such an instinct eventually became universal in the early human population.
Religious Behavior and Genetics
The universality of religious behavior suggests that, as with language, it is mediated by specialized structures in the brain. Language is known to be supported by neural circuitry in certain regions of the brain because, if these regions are damaged even minutely, specific defects appear in a patient’s linguistic abilities. No such dedicated regions have yet been identified with certainty for the neural circuitry that may underlie religious behavior. Excessive religiosity is a well-known symptom of temporal lobe epilepsy and could reflect the activation of neural circuits associated with religious behavior. But there is no agreement on this point, and the search for such circuitry in people who don’t suffer from epilepsy is “suggestive but not conclusive,” according to the neurologist Steven Schachter.39 It could be that religious behavior itself does not require a dedicated brain region large enough to be detectable by present methods.
The fact that religious behavior is universal strongly suggests that it is an adaptation, meaning a trait shaped by natural selection. If it is an adaptation, it must have a genetic basis, such as a suite of genes that are activated during development and wire up the neural circuits needed to induce the behavior. Identification of such genes would be the best possible proof that religious behavior has an evolutionary basis. The lack of any progress in this direction so far is not particularly surprising; the genes that underlie complex diseases have started to be identified only recently and funds to support such expensive efforts are not available for studying nonmedical complex traits.
An indirect approach to the genetic basis of religious behavior is through psychological studies of adopted children and of twins. Such studies pick up traits that vary in the population, such as height, and estimate how much of the variation is due to environmental factors and how much to genetics. But the studies cannot pick up the presence of genes that don’t vary; genes for learning language, for example, are apparently so essential that there is almost no variation in the population, since everyone can learn language. If religious behavior is equally necessary for survival, then the genes that underlie it will be the same in everyone, and no variation will be detectable.
Religious behavior itself is hard to quantify, but studies of religiosity—the intensity with which the capacity for religious behavior is implemented—have shown that it is moderately heritable, meaning that genes contribute s
omewhat, along with environmental factors, to the extent of the trait’s variation in the population. “Religious attitudes and practices are moderately influenced by genetic factors,” a large recent study concludes.40 Another survey finds that “the heritability of religiousness increases from adolescence to adulthood,” presumably because the influence of environmental factors decreases in adulthood (when you leave home you go to church if you want to, not because your parents say so).41 The aspects of religiosity that psychologists measure include factors like the frequency of church attendance and the importance assigned to religious values. Their studies show that there are genetic influences at work on the intensity of religious behavior, but do not yet reach to the heart of the issue, that of probing the neural circuitry for learning and practicing the religion of one’s community.
In the absence of direct evidence about the genes underlying religious behavior, its evolutionary basis can be assessed only indirectly. The effect of cultural learning in religion is clear enough, as shown by the rich variety of religions around the world. It’s the strong commonalities beneath the variations that are the fingerprints of an innate learning mechanism. These common features seem very unlikely to have persisted in all societies for the 2,000 generations that have elapsed during the 50,000 years since the ancestral human population dispersed from its African homeland, unless they have a genetic basis. This is particularly true given the complexity of religious behavior, and its rootedness in the emotional levels of the brain.
To no less an observer than Darwin himself it seemed that religion was like an instinctive behavior, one that the mind is genetically primed to learn as indelibly as the fear of heights or the horror of incest. His two great books on evolution, Origin of Species and Descent of Man, have nothing directly to say about religion but in his autobiography, written in his old age, he was more explicit about this controversial topic. He wrote, “Nor must we overlook the probability of the constant inculcation in a belief in God on the minds of children producing so strong and perhaps an inherited effect on their brains not yet fully developed, that it would be as difficult for them to throw off their belief in God, as for a monkey to throw off its instinctive fear and hatred of a snake.”42
The Faith Instinct Page 5