aminotes:

”(…) Error Management Theory suggests that, in your inference, you can make a “Type I” error of false positive or “Type II” error of false negative, and these two types of error carry vastly different consequences and costs. The cost of a false-positive error is that you become paranoid. You are always looking around and behind your back for predators and enemies that don’t exist. The cost of a false-negative error is that you are dead, being killed by a predator or an enemy when you least expect them. Obviously, it’s better to be paranoid than dead, so evolution should have designed a mind that overinfers personal, animate, and intentional forces even when none exist.

Different theorists call this innate human tendency to commit false-positive errors rather than false-negative errors (and as a consequence be a bit paranoid) “animistic bias” or “the agency-detector mechanism.” These theorists argue that the evolutionary origins of religious beliefs in supernatural forces may have come from such an innate cognitive bias to commit false-positive errors rather than false-negative errors, and thus overinfer personal, intentional, and animate forces behind otherwise perfectly natural phenomena. (…)

In this view, religiosity (the human capacity for belief in supernatural beings) is not an evolved tendency per se; after all, religion in itself is not adaptive. It is instead a byproduct of animistic bias or the agency-detector mechanism, the tendency to be paranoid, which is adaptive because it can save your life. Humans did not evolve to be religious; they evolved to be paranoid. And humans are religious because they are paranoid. (…)”

— Satoshi Kanazawa, Why do we believe in God?, Psychology Today, March 28, 2008. (More). See also: Martie G. Haselton and David M. Buss, Error Management Theory: A New Perspective on Biases in Cross-Sex Mind Reading, University of Texas at Austin (pdf)