It was a fall day in 1930, and the famous American philosopher and historian William Durant was raking leaves in his yard. A despondent stranger walked up and shocked Durant by confessing he was planning to commit suicide unless Durant could give him "one good reason" to live. Flustered, Durant gave a feeble reply: "I bade him get a job-but he had one; to eat a good meal-but he was not hungry; he left visibly unmoved...