Have you ever stopped to consider what a brilliant mind reader you are? If someone in your field of view experiences a sudden happy thought or a wave of anger, you do not need to be told. You just seem to know. Of course, this ability is not based on psychic powers but on the reading of small clues: a distinctive curl of the lips for joy, a clenching of the jaw for pique. Think of how a mime, working without words, can evoke an entire story, with multiple characters, each with their own intentions, beliefs and desires—all because we are remarkably skilled at imagining the mental lives of others.