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Brenda X is a favorite of the ward nurses because she's no trouble. While the other patients jabber and pace and squabble, Brenda just reads her story book, scribbling notes on magazine inserts. The hero of her book lived a life of courage. He faced his horrific death with so much boldness and grace that, in dying, he vanquished his killers—vanquished death itself. When Brenda is not reading about her hero she is addressing him directly in prayer. The hero never peeps in reply. But Brenda knows that he's listening and that his power stretches out forever and that he loves her like his own dear child. Brenda lives in the asylum and cannot leave because she thinks her story book is the truest thing in the world—truer than history or science. Brenda's puzzled therapists ask why she thinks this. "I just know," she replies. "I have faith."
Brenda is no more real than the hero of her story. Like Yahweh fashioning Adam from dirt, I forged Brenda out of paper and ink. Aside from this, there is only one difference between Brenda and an ordinary religious person. In my little fiction, Brenda is deemed insane for worshipping the wrong character in the wrong story book. Brenda doesn't worship Jesus Christ. She worships the hero of some other book—one of countless protagonists modeled on the example of Christ, maybe long-suffering Uncle Tom or perhaps the messianic Neo from the graphic novel version of The Matrix.
I haven't told my Brenda story to antagonize believers. I did it to accentuate a fact that's very impressive once you've moved past its familiarity: Religions are made out of stories. Flip through the holy books of any religion and you will be flipping through an anthology of absorbing stories: The Fall, the Flood, the Archangel Gabriel seizing Muhammad by the throat, Prometheus stealing Olympian fire. Of course, some Christians might bristle at the implications of my Brenda story. But many of them would be quick to agree that other religions—Hinduism, Islam, Zoroastrianism—are based merely on stories.
Religion is a human universal, present in one form or another in all of the societies that anthropologists have visited and archaeologists have dug up. Since it is not plausible that religion just happened to develop independently in many thousands of different cultures, Homo sapiens must have already been a spiritual ape when our ancestors began streaming out of Africa.
But why did we evolve to be religious? How did dogmatic faith in imaginary beings not diminish our ability to survive and reproduce? How could the frugal mechanisms of natural selection not have worked against religion, given the high price of religious sacrifices, rituals, prohibitions, taboos, and commandments?
Some evolutionary thinkers, including leading lights like Daniel Dennett and Richard Dawkins, focus relentlessly on the black side of religious behavior. They think that religion is the result of a tragic evolutionary glitch. Both Dennett and Dawkins view religion as a mental parasite (as Dawkins memorably put it, religion is "a virus of the mind"), and a noxious one at that. For them, human life would be a lot better if the mental parasite of religion could simply be eradicated.
I'm not so sure. In his groundbreaking book, Darwin's Cathedral, biologist David Sloan Wilson proposes that religion emerged as a stable part of all human societies for a simple reason: it made them work better. Human groups that happened to possess a faith instinct so thoroughly dominated non-religious competitors that religious tendencies became deeply entrenched in our species.
Atheists are often dismayed that intelligent believers can entertain patently irrational beliefs. From the atheist perspective, the earth's faithful are like billions of foolish Don Quixotes jousting with windmills-all because, like Quixote, they can't see that their favorite story books are exactly that.
But Wilson points out that "elements of religion that appear irrational and dysfunctional often make perfectly good sense when judged by the only appropriate gold standard as far as evolutionary theory is concerned-what they cause people to do." And what they generally cause people to do is to behave more decently toward members of the group (co-religionists) while vigorously asserting the group's interests against competitors. As the German evolutionist Gustav Jager argued in 1869, religion can be seen as "a weapon in the [Darwinian] struggle for survival."
As Jager's language suggests, none of this should be construed to suggest that religion is-on the whole-a good thing. There are good things about religion, including the way its stories bind people into more harmonious collectives. But there is an obvious dark side to religion too: the way it is so readily weaponized. Religion draws co-religionists together and drives those of different faiths apart.
Jonathan Gottschall is the author of The Storytelling Animal: How Stories Make Us Human.
