Kurt Vonnegut Jr. (1922–2007) was an American writer famed for darkly comic, humane novels including Slaughterhouse-Five and Cat’s Cradle. In his 1982 novel Deadeye Dick he quoted the “to be is to do” joke as graffiti scrawled on a wall, crediting Socrates, Sartre and Sinatra — not himself. Because his name is a magnet for clever, quotable lines, the internet has since promoted him from the person who copied down the joke to the person who supposedly coined it.