Why God exists??

A fascinating article in New York Times titled "Darwin's God" By ROBIN MARANTZ HENIG, March 4, 2007 :

In the world of evolutionary biology, the question is not whether God exists but why we believe in him. Is belief a helpful adaptation or an evolutionary accident?

there seems an inherent human drive to believe in something transcendent, unfathomable and otherworldly, something beyond the reach or understanding of science.

Scientists studying the evolution of religion 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.

Evolutionary Byproduct

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.

It means our brains are primed for it, ready to presume the presence of agents even when such presence confounds logic.

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.

Gods, by virtue of their strange physical properties and their mysterious superpowers, make fine candidates for causes of many of these unusual events.”

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.

Evolutionary Adaptation

Intriguing as the "byproduct" 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.

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.”

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.