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

Long long ago, in an environment far 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 that 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 conspiracists, 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 for 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 for 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 insure 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.

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