Psychology is the study of human behavior. It is a serious and worthy endeavor that has given us scientific knowledge of the ways our minds make sense of the world. Yet, as cartoonist Grady Klein and psychologist Danny Oppenheimer point out, the study of human experience can also be often really funny. This is the field, after all, that brought us drooling dogs, snacking rats, and "Freudian slips." With detailed observations on perception, stress,...