Many people live one life. Jack Dreyfus has had two. The first was when he founded the Dreyfus Fund. He became known as the most singular and effective personality to appear on Wall Street since the days of Joseph Kennedy and Bernard Baruch (Life magazine). The author's second life began in 1963 when, in the midst of a severe depression, he asked his physician to let him try a medicine usually prescribed for epilepsy. The medicine (phenytoin) brought him back to good health almost overnight. When he saw six other people have similar results, he realized he had an obligation to investigate further.