Today’s topic: What do you think of the theory that religious belief and experience are wired through evolution?

Homo religious

Point: Michael Shermer

Did humans evolve to be religious and believe in God? In the most general sense, yes, we did. Here’s what happened.

Long ago, in an environment far away from the modern world, humans evolved to find meaningful causal patterns in nature to make sense of the world, and infuse many of those patterns with intentional agency, some of which became animistic spirits and powerful gods. And as a social primate species, we also evolved social organizations designed to promote group cohesiveness and enforce moral rules.

People believe in God because we are pattern-seeking primates. We connect A to B to C, and often A really is connected to B, and B really is connected to C. This is called association learning. But we do not have a false-pattern-detection device in our brains to help us discriminate between true and false patterns, and so we make errors in our thinking. A Type I error is believing a pattern is real when it is not (a false positive) and a Type II error is not believing a pattern is real when it is (a false negative).

Imagine you are a hominid on the planes of Africa and you hear a rustle in the grass. Is it a dangerous predator or just the wind? If you assume it is a dangerous predator and it is just the wind, you have made a Type I error, but to no harm. But if you believe the rustle in the grass is just the wind when it is a dangerous predator, there’s a good chance you’ll be lunch and thereby removed from your species’ gene pool. Thus, there would have been a natural selection for those hominids who tended to believe that all patterns are real and potentially dangerous.

I call this process “patternicity” (the tendency to find meaningful patterns in random noise) and “agenticity” (the tendency to believe that the world is controlled by invisible intentional agents who may mean us harm). This, I believe, is the basis for the belief in souls, spirits, ghosts, gods, demons, angels, aliens, intelligent designers, government conspiracy theorists and all manner of invisible agents intending to harm us or help us.

People are religious because we are social and we need to get along. The moral sentiments in humans and moral principles in human groups evolved primarily through the force of natural selection operating on individuals, and secondarily through the force of group selection operating on populations. The moral sense (the psychological feeling of doing “good” in the form of positive emotions such as righteousness and pride) evolved out of behaviors that were selected because they were good either for the individual or for the group. An immoral sense (the psychological feeling of doing “bad” in the form of negative emotions such as guilt and shame) evolved out of behaviors that were selected because they were bad either for the individual or for the group.

While cultures may differ on what behaviors are defined as good or bad, the moral sense of feeling good or feeling bad about behavior X (whatever X may be) is an evolved human universal. The codification of moral principles out of the psychology of the moral sentiments evolved as a form of social control to ensure the survival of individuals within groups and the survival of human groups themselves. Religion was the first social institution to canonize moral principles, and God -- as an explanatory pattern for the world -- took on new powers as the ultimate enforcer of the rules.

Thus it is that people are religious and believe in God.

Michael Shermer is publisher of Skeptic magazine, a monthly columnist for Scientific American and the author of, most recently, “The Mind of the Market.”

We die, therefore we are religious

Counterpoint: Francisco J. Ayala

The formal name of the human species is Homo sapiens, or “knowing human.” As a consequence of evolution, ours is the most intelligent species on Earth. A likely explanation of how our exalted intelligence came to be has to do with our ancestors of 2 million years ago, known as Homo habilis, who started to make very simple stone tools. Making tools requires seeing such objects as “tools,” in other words, something to be used for a particular purpose: a knife for cutting, an arrow for hunting and so on. Seeing something as a tool requires forming mental images of realities not present: the deer I’ll seek to kill and the flesh I’ll cut for eating. In turn, forming mental images of things not present requires advanced intelligence, which is why so few animals make tools, and the tools they do make haven’t developed into anything resembling the advanced technologies of our species.

The evolution scenario suggests that those more intelligent among our remote ancestors were able to make better tools. And those who made better tools survived better because they got more food and were more effective at killing their enemies or defending themselves. Therefore, those more intelligent left more descendants, and genes for higher intelligence increased in frequency for thousands and thousands of years among our ancestors.

Our intelligence is curious: We want to understand the world around us, how things happen and why they happen. We seek causal explanations of natural events. Before modern science came of age in the 17th century, humans attributed natural events for which they did not know the explanation to supernatural agents. Spirits or gods caused rain and drought, floods and storms, earthquakes and volcanic eruptions, surely in retribution for human deeds. These beliefs would often lead to worship and rituals.

Seeking causal explanations for events in the natural world was one source of religious beliefs and practices. Humans live in complex societies, which need to be governed by laws and moral norms. Seeking justification for moral norms and social laws was another source of religious faith and cults. Israelites, for example, were told by Moses to observe the Ten Commandments because these were ordered by God.

But there is one more source of religion that also depends on our evolution-endowed intelligence: self-awareness and its consequence, death-awareness. Except for young infants, every person is conscious of existing as a distinct individual, different from other people and from the environment. Self-awareness is the most immediate and unquestionable reality of our experience.

Moreover, we humans are the only animals with full experience of self-awareness, which implies death-awareness. If I know I exist as a distinct human individual, I know I will die because I see other people die. Because we ceremonially bury our dead, we know humans are the only animals that are death-aware. All human societies have burial rituals, although the rites are very diverse. Ritual burial follows from death-awareness: If I know I will die, I will treat other dead humans with such respect because I want to be treated this way when I die.

Because we humans are aware of the transitory character of our existence, we develop anxiety over death. This anxiety is at least in part alleviated by religious beliefs and rituals, which give meaning to one’s own life even though life will end. Anxiety about death is further relieved in the many religions that attribute immortality to the soul, either through successive reincarnations or in the form of life beyond death.

Evolution, by making humans intelligent, predisposed us to be religious.

Francisco J. Ayala, a biology professor at UC Irvine, is a member of the U.S. National Academy of Sciences and was awarded the U.S. National Medal of Science in 2001.