In Rational Mysticism, acclaimed journalist John Horgan embarks on an adventure of discovery, investigating the ways in which scientists, theologians, and philosophers are attempting to formulate an empirical explanation of spiritual enlightenment. Horgan visits and interviews a fascinating Who's Who of experts, including theologian Huston Smith; Andrew Newberg, explorer of the brain's "God module"; Ken Wilber, a transpersonal psychologist and Buddhist; psychedelic pharmacologist Alexander Shulgin; Oxford-educated psychologist and Zen practitioner Susan Blackmore; and postmodern shaman Terence McKenna. Horgan also explores the effects of reputed enlightenment-inducing techniques such as fasting, meditation, prayer, sensory deprivation, and drug trips. In his lively and thought-provoking inquiry, Horgan finds surprising connections among seemingly disparate disciplines, not the least of which is a shared awe of the nature of the universe.