Superstitious behavior is the most obvious form. John McEnroe notoriously refused to step on the white lines of a tennis court between points. Wade Boggs insisted on eating a chicken dinner before every Boston Red Sox game. Presidential candidate Barak Obama played a game of basketball the morning of his victory in the Iowa primary, and continued the tradition the day of every following primary. Superstitious habits are common. Do you ever cross your fingers, knock on wood, avoid walking under ladders, or step around black cats?