The NYTimes magazine has an excellent article on the controversy within science as to the meaning of God. This is different from the cultural controversy as to the validity of Revelation because it is concerned with why religion may have evolved as opposed to whether it evolved.
Lost in the hullabaloo over the neo-atheists is a quieter and potentially more illuminating debate. It is taking place not between science and religion but within science itself, specifically among the scientists studying the evolution of religion. These scholars tend to agree on one point: that religious belief is an outgrowth of brain architecture that evolved during early human history. What they disagree about is why a tendency to believe evolved, whether it was because belief itself was adaptive or because it was just an evolutionary byproduct, a mere consequence of some other adaptation in the evolution of the human brain.
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?
With respect to this question, there are two general camps. The first is the byproduct theorists who believe that religion is the byproduct of traits that are themselves adaptive, but that religion itself serves no adaptive purpose. The second is the adaptationists who, either on a group or an individual level, argue that evolution is adaptive.
Scott Atran is enumerated as one of the byproduct theorists:
Atran saw such questions as a puzzle when applied to religion. So many aspects of religious belief involve misattribution and misunderstanding of the real world. Wouldn't this be a liability in the survival-of-the-fittest competition? To Atran, religious belief requires taking "what is materially false to be true" and "what is materially true to be false." One example of this is the belief that even after someone dies and the body demonstrably disintegrates, that person will still exist, will still be able to laugh and cry, to feel pain and joy. This confusion "does not appear to be a reasonable evolutionary strategy," Atran wrote in "In Gods We Trust: The Evolutionary Landscape of Religion" in 2002. "Imagine another animal that took injury for health or big for small or fast for slow or dead for alive. It's unlikely that such a species could survive." He began to look for a sideways explanation: if religious belief was not adaptive, perhaps it was associated with something else that was.
Other scientists such as David Sloane Wilson are adaptationists:
One of the most vocal adaptationists is David Sloan Wilson, an occasional thorn in the side of both Scott Atran and Richard Dawkins. Wilson, an evolutionary biologist at the State University of New York at Binghamton, focuses much of his argument at the group level. "Organisms are a product of natural selection," he wrote in "Darwin's Cathedral: Evolution, Religion, and the Nature of Society," which came out in 2002, the same year as Atran's book, and staked out the adaptationist view. "Through countless generations of variation and selection, [organisms] acquire properties that enable them to survive and reproduce in their environments. My purpose is to see if human groups in general, and religious groups in particular, qualify as organismic in this sense."
Read the whole thing. I feel like they really clearly lay out where people stand on the scientific arguements, and they cite most of the relevant books on the subject.
Bipolar disorder makes a nice parallel to religion and the purported value of religious experiences.
The bipolar sufferer has organic defects in the operation of social emotions, the ones that reward you when you do social good and punish you when you do social ill. Joy, shame, pride, and guilt are among the most familiar such emotions.
Now, consider what happens when the sufferer's emotional mechanism goes awry. She starts feeling bad for no good reason, which drives her to keep trying to correct her own behavior in hopes of stopping those bad feelings. All of her efforts are in vain, of course, since her bad feelings are independent of her actions.
Later the bad feelings pass on their own.
Later still, good feelings arrive. She strives to keep the good feelings going by doing whatever seems to bring on better feelings, and soon enough she is fully manic.
By the time the good feelings go away, she may be addicted to heroin, pregnant, HIV positive, in jail, and badly battered.
Her disorder drives her behavior to both extremes, neither of which is the least bit adaptive. Her emotions are misinforming her. Believing her feelings are real is a serious mistake.
Now look at religions and the good and bad feelings they can bring people. These are as purely maladaptive and destructive as manic-depression.
Religious people are sorely in need of clinical treatment.