In the 1940s, my parents lived in a small Georgia town where my father had his dental practice. He was friends with the chief of police and on good terms with many of the patrolmen. The police station was on the route between our house and my father’s office. When he walked home from work, it was not unusual for him to stop in and share pleasantries with whoever was on duty. Dad loved to tell the story about one such visit during which one of the patrolmen expressed concern about his appearance. “Doc,” he said, “you look worried. Somethin’...