While other scientists are fighting off the claims of creationists, British biology professor Lewis Wolpert ponders why we are all believers. He notes that 70 percent of Americans believe in angels; almost half the population accepts the validity of astrology; and even award-winning academics avoid the number 13 or refuse to walk under ladders. Dr. Wolpert draws on the findings of evolutionary psychology to posit a relationship between early human language and tool making and the development of cause-and-effect beliefs. Wolpert's lucid explanations never evidence any mockery of religious belief, but he does regard science as the most valuable, valid belief system.