[ Mon. Apr. 9. 2007 ]

Life is full of surprises, but it's rare to reach for a carafe of wine and find your hand clutching a bottle of milk -- and even rarer, you'd think, to react by deciding the milk was actually what you wanted all along.

Yet something like that happened when scientists in Sweden asked people to choose which of two women's photos they found most attractive. After the subject made his choice, whom we'll call Beth, the experimenter turned the chosen photo face down. Sliding it across the table, he asked the subject the reasons he chose the photo he did. But the experimenter was a sleight-of-hand artist. A copy of the unchosen photo, "Grizelda," was tucked behind Beth's, so what he actually slid was the duplicate of Grizelda, palming Beth.

Few subjects batted an eye. Looking at the unchosen Grizelda, they smoothly explained why they had chosen her ("She was smiling," "she looks hot"), even though they hadn't.

In 1966, Time magazine asked, "Is God Dead?" Even then, the answer was no, and with the rise of religion in the public square, the question now seems ludicrous. In one of those strange-bedfellows things, it is science that is shedding light on why belief in God will never die, at least until humans evolve very different brains, brains that don't (as they did with Beth and Grizelda) interpret unexpected and even unwanted outcomes as being for the best.

"Belief in God," says Daniel Gilbert, professor of psychology at Harvard University, "is compelled by the way our brains work."

As shown in the Grizelda-and-Beth study, by scientists at Lund University and published this month in Science, brains have a remarkable talent for reframing suboptimal outcomes to see setbacks in the best possible light. You can see it when high-school seniors decide that colleges that rejected them really weren't much good, come to think of it.

You can see it, too, in experiments where Prof. Gilbert and colleagues told female volunteers they would be working on a task that required them to have a likeable, trustworthy partner. They would get a partner randomly, by blindly choosing one of four folders, each containing a biography of a potential teammate. Unknown to the volunteers, each folder contained the same bio, describing an unlikable, untrustworthy person.

The volunteers were unfazed. Reading the randomly chosen bio, they interpreted even negatives as positives. "She doesn't like people" made them think of her as "exceptionally discerning." And when they read different bios, they concluded their partner was hands-down superior. "Their brains found the most rewarding view of their circumstances," says Prof. Gilbert.

The experimenter then told the volunteer that although she thought she was choosing a folder at random, in fact the experimenter had given her a subliminal message so she would pick the best possible partner. The volunteers later said they believed this lie, agreeing that the subliminal message had led them to the best folder. Having thought themselves into believing they had chosen the best teammate, they needed an explanation for their good fortune and experienced what Prof. Gilbert calls the illusion of external agency.

"People don't know how good they are at finding something desirable in almost any outcome," he says. "So when there is a good outcome, they're surprised, and they conclude that someone else has engineered their fate" -- a lab's subliminal message or, in real life, God.

Religion used to be ascribed to a wish to escape mortality by invoking an afterlife or to feel less alone in the world. Now, some anthropologists and psychologists suspect that religious belief is what Pascal Boyer of Washington University, St. Louis, calls in a 2003 paper "a predictable by-product of ordinary cognitive function."

One of those functions is the ability to imagine what Prof. Boyer calls "nonphysically present agents." We do this all the time when we recall the past or project the future, or imagine "what if" scenarios involving others. It's not a big leap for those same brain mechanisms to imagine spirits and gods as real.

Another God-producing brain quirk is that although many things can be viewed in multiple ways, the mind settles on the most rewarding. Take the Necker cube, the line drawing that shifts orientation as you stare at it. (A cool version is at If you reward someone for seeing the cube one way, however, his brain starts seeing it that way only. The cube stops flipping.

There are only two ways to see a Necker cube, but loads of ways to see a hurricane or a recovery from illness. The brain "tends to search for and hold onto the most rewarding view of events, much as it does of objects," Prof. Gilbert writes on the Web site Edge. It is much more rewarding to attribute death to God's will, and to see in disasters hints of the hand of God.

Prof. Gilbert once asked a religious colleague how he felt about helping to discover that people can misattribute the products of their own minds to acts of God. The reply: "I feel fine. God doesn't want us to confuse our miracles with his."