As V.S. Ramachandran explained in his 1998 book "Phantoms in the Brain," patients with temporal lobe epilepsy may experience a variety of symptoms that include an obsessive preoccupation with religion and the intensified and narrowed emotional responses that are characteristic of mystical experience. (St. Teresa of Avila, Dostoevski, van Gogh and St. Paul are believed by some historians and scientists to have suffered from the affliction.) Observing these symptoms, scientists have established that some circuits in the temporal lobe are involved in religious experience.

For now, that's about as specific as neurologists can get regarding the biological basis of religion. No one can say whether these circuits have evolved primarily to evoke religious experience. No one can say whether religious impulses originate in some other part of the brain and then make their way to the temporal lobe. No one can solve the chicken-and-egg question of whether religious experience strengthens these circuits, or neural activity makes mystical vision possible. And no one can say whether or how the neurological activity associated with mystical experience is related to the everyday, earthbound experience of religious devotion.

For evolutionary biologists such as E.O. Wilson, however, the mere fact that "the emotions that accompany religious ecstasy clearly have a neurobiological source" helps to confirm that "much if not all religious behavior could have arisen from evolution by natural selection." These observations come from 1998's "Consilience," which includes a brief discussion of religious experience in terms of evolutionary biology. For the discipline's specific application to the matter at hand, however, I've seen nothing that matches the fury of "The God Part of the Brain," which perhaps explains why it's earned something of a cult following.

To be clear from the get-go: This book is a screed, full of bad writing, sloppy thinking and slipshod research. Yet some passages make for compelling reading, yielding the kind of pleasures often found in outsider art. Alper's book is powerful not because of its truth, but because of its scope and ambition -- which rival that of "Throne of the Third Heaven of the Nation's Millennium General Assembly," the massive altar, made of aluminum foil, light bulbs, pins and bottle caps and telling the story of the universe, found in the garage of a janitor for the General Services Adminstration in Washington after his death in 1964.

Although Alper does not provide details of his early life or his religious or educational background, he states that he has been on a spiritual quest at least since his "mid-teens, those years of which Wordsworth wrote, 'bring upon the philosophic mind'" when "I realized that my life's primary pursuit would be -- if it were at all possible -- to acquire clear and distinct knowledge of God." Sometime between that period and his 21st birthday, Alpert had a bad LSD trip that mired him in anxiety and depression, which were alleviated by medication.

His suffering made him an empiricist: "The fact ... that my conscious self had been so ravaged, scrambled and defiled in the past year and a half convinced me that there was no fixed or eternal essence in me." This conviction led him to decide that "if spirits or souls truly existed, they should not be able to be affected by matter." And his belief that the soul is a "manifestation of some strictly physical phenomenon" led logically to the idea that there must be a "God part of the brain."

Maya Angelou reads from "The Heart of a Woman"