"Picture this: You're a human being living many thousands of years ago. You're out on the plains of the Serengeti, sitting around, waiting for an antelope to walk by so you can kill it for dinner. All of a sudden, you see the grasses in front of you rustling. What do you do? Do you stop and think about what might be causing the rustling (the wind or a lion, for example), or do you immediately take some kind of action?
"On the plains of the Serengeti, it would be better to not sit around and reflect. People who took their time got selected out," Clark told Live Science. Humans who survived to procreate were those who had developed what evolutionary scientists call a hypersensitive agency-detecting device, or HADD, he said.
In short, HADD is the mechanism that lets humans perceive that many things have "agency," or the ability to act of their own accord. This understanding of how the world worked facilitated the rapid decision-making process that humans had to go through when they heard a rustling in the grass. (Lions act of their own accord. Better run.)
But in addition to helping humans make rational decisions, HADD may have planted the seeds for religious thought. In addition to attributing agency to lions, for example, humans started attributing agency to things that really didn't have agency at all. [
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"You might think that raindrops aren't agents," Clark said. "They can't act of their own accord. They just fall. And clouds just form; they're not things that can act. But what human beings have done is to think that clouds are agents. They think [clouds] can act," Clark said of early humans.
And then humans took things to a whole new level. They started attributing meaning to the actions of things that weren't really acting of their own accord. For example, they thought raindrops were "acting for a purpose," Clark said.
Acting for a purpose is the basis for what evolutionary scientists call the Theory of Mind (ToM) — another idea that's often cited in discussions about the origins of religion. By attributing intention or purpose to the actions of beings that did have agency, like other people, humans stopped simply reacting as quickly as possible to the world around them — they started anticipating what other beings' actions might be and planning their own actions accordingly. (Being able to sort of get into the mind of another purposeful being is what Theory of Mind is all about.)
ToM was very helpful to early humans. It enabled them to discern other people's positive and negative intentions (e.g., "Does that person want to mate with me or kill me and steal my food?"), thereby increasing their own chances of survival.
But when people started attributing purpose to the actions of nonactors, like raindrops, ToM took a turn toward the supernatural. [
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"The roaring threat of a thunderstorm or the devastation of a flood is widely seen across cultures as the product of a dangerous personal agent in the sky or river, respectively," said Allen Kerkeslager, an associate professor in the Department of Theology and Religious Studies at Saint Joseph's University in Philadelphia."Likewise, the movements of the sun, moon and stars are widely explained as the movements of personal agents with extraordinary powers,"Kerkeslager told Live Science in an email.
This tendency to explain the natural world through the existence of
beings with supernatural powers — things like gods, ancestral spirits, goblins and
fairies — formed the basis for religious beliefs, according to many cognitive scientists. Collectively, some scientists refer to HADD and ToM as the "god faculty," Clark said.
In fact, human beings haven't evolved past this way of thinking and making decisions, he added.
"Now, we understand better that the things we thought were agents aren't agents," Clark said. "You can be educated out of some of these beliefs, but you can't be educated out of these cognitive faculties. We all have a hyperactive agency-detecting device. We all have a theory of mind."
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