Which is the better biological explanation for a belief in God — evolutionary adaptation or neurological accident? Is there something about the cognitive functioning of humans that makes us receptive to belief in a supernatural deity? And if scientists are able to explain God, what then? Is explaining religion the same thing as explaining it away? Are the nonbelievers right, and is religion at its core an empty undertaking, a misdirection, a vestigial artifact of a primitive mind? Or are the believers right, and does the fact that we have the mental capacities for discerning God suggest that it was God who put them there?
In short, are we hard-wired to believe in God? And if we are, how and why did that happen?
Some evolutionary biologists think that our belief engine developed as a side-adaption of an evolutionary adaptation that helped us survive:
Hardships of early human life favored the evolution of certain cognitive tools, among them the ability to infer the presence of organisms that might do harm, to come up with causal narratives for natural events and to recognize that other people have minds of their own with their own beliefs, desires and intentions. Psychologists call these tools, respectively, agent detection, causal reasoning and theory of mind.
Agent detection evolved because assuming the presence of an agent — which is jargon for any creature with volitional, independent behavior — is more adaptive than assuming its absence. If you are a caveman on the savannah, you are better off presuming that the motion you detect out of the corner of your eye is an agent and something to run from, even if you are wrong. If it turns out to have been just the rustling of leaves, you are still alive; if what you took to be leaves rustling was really a hyena about to pounce, you are dead.
A classic experiment from the 1940s by the psychologists Fritz Heider and Marianne Simmel suggested that imputing agency is so automatic that people may do it even for geometric shapes. For the experiment, subjects watched a film of triangles and circles moving around. When asked what they had been watching, the subjects used words like “chase” and “capture.” They did not just see the random movement of shapes on a screen; they saw pursuit, planning, escape.
So if there is motion just out of our line of sight, we presume it is caused by an agent, an animal or person with the ability to move independently. This usually operates in one direction only; lots of people mistake a rock for a bear, but almost no one mistakes a bear for a rock.
What does this mean for belief in the supernatural? It means our brains are primed for it, ready to presume the presence of agents even when such presence confounds logic. “The most central concepts in religions are related to agents,” Justin Barrett, a psychologist, wrote in his 2004 summary of the byproduct theory, “Why Would Anyone Believe in God?” Religious agents are often supernatural, he wrote, “people with superpowers, statues that can answer requests or disembodied minds that can act on us and the world.”
A second mental module that primes us for religion is causal reasoning. The human brain has evolved the capacity to impose a narrative, complete with chronology and cause-and-effect logic, on whatever it encounters, no matter how apparently random. “We automatically, and often unconsciously, look for an explanation of why things happen to us,” Barrett wrote, “and ‘stuff just happens’ is no explanation. Gods, by virtue of their strange physical properties and their mysterious superpowers, make fine candidates for causes of many of these unusual events.” The ancient Greeks believed thunder was the sound of Zeus’s thunderbolt. Similarly, a contemporary woman whose cancer treatment works despite 10-to-1 odds might look for a story to explain her survival. It fits better with her causal-reasoning tool for her recovery to be a miracle, or a reward for prayer, than for it to be just a lucky roll of the dice.
A third cognitive trick is a kind of social intuition known as theory of mind. It’s an odd phrase for something so automatic, since the word “theory” suggests formality and self-consciousness. Other terms have been used for the same concept, like intentional stance and social cognition. One good alternative is the term Atran uses: folkpsychology.
Folkpsychology, as Atran and his colleagues see it, is essential to getting along in the contemporary world, just as it has been since prehistoric times. It allows us to anticipate the actions of others and to lead others to believe what we want them to believe; it is at the heart of everything from marriage to office politics to poker. People without this trait, like those with severe autism, are impaired, unable to imagine themselves in other people’s heads.
The process begins with positing the existence of minds, our own and others’, that we cannot see or feel. This leaves us open, almost instinctively, to belief in the separation of the body (the visible) and the mind (the invisible). If you can posit minds in other people that you cannot verify empirically, suggests Paul Bloom, a psychologist and the author of “Descartes’ Baby,” published in 2004, it is a short step to positing minds that do not have to be anchored to a body. And from there, he said, it is another short step to positing an immaterial soul and a transcendent God.
Others think that religious belief developed not as an "accident" of another evolutionary process but because religion itself provided a concrete benefit to those who held religious beliefs:
Intriguing as the spandrel logic might be, there is another way to think about the evolution of religion: that religion evolved because it offered survival advantages to our distant ancestors. This is where the action is in the science of God debate, with a coterie of adaptationists arguing on behalf of the primary benefits, in terms of survival advantages, of religious belief.
The trick in thinking about adaptation is that even if a trait offers no survival advantage today, it might have had one long ago. This is how Darwinians explain how certain physical characteristics persist even if they do not currently seem adaptive — by asking whether they might have helped our distant ancestors form social groups, feed themselves, find suitable mates or keep from getting killed. A facility for storing calories as fat, for instance, which is a detriment in today’s food-rich society, probably helped our ancestors survive cyclical famines.
So trying to explain the adaptiveness of religion means looking for how it might have helped early humans survive and reproduce. As some adaptationists see it, this could have worked on two levels, individual and group. Religion made people feel better, less tormented by thoughts about death, more focused on the future, more willing to take care of themselves. As William James put it, religion filled people with “a new zest which adds itself like a gift to life . . . an assurance of safety and a temper of peace and, in relation to others, a preponderance of loving affections.”
Such sentiments, some adaptationists say, made the faithful better at finding and storing food, for instance, and helped them attract better mates because of their reputations for morality, obedience and sober living. The advantage might have worked at the group level too, with religious groups outlasting others because they were more cohesive, more likely to contain individuals willing to make sacrifices for the group and more adept at sharing resources and preparing for warfare.
It is quite an interesting read. And lest you think that the folks doing this work are atheists out to destroy religion:
And one prominent member of the byproduct camp, Justin Barrett, is an observant Christian who believes in “an all-knowing, all-powerful, perfectly good God who brought the universe into being,” as he wrote in an e-mail message. “I believe that the purpose for people is to love God and love each other.”
At first blush, Barrett’s faith might seem confusing. How does his view of God as a byproduct of our mental architecture coexist with his Christianity? Why doesn’t the byproduct theory turn him into a skeptic?
“Christian theology teaches that people were crafted by God to be in a loving relationship with him and other people,” Barrett wrote in his e-mail message. “Why wouldn’t God, then, design us in such a way as to find belief in divinity quite natural?” Having a scientific explanation for mental phenomena does not mean we should stop believing in them, he wrote. “Suppose science produces a convincing account for why I think my wife loves me — should I then stop believing that she does?”