Between 1692 and 1693, Puritans in the British colony in Salem, Massachusetts, became hysterical believing that they were under attack by people in league with the devil practicing the sinister magic of witchcraft. What began with the strange physical ailments of three young girls quickly grew into a panic amongst the settlers. What kind of irrational fear would condemn 19 people, overwhelmingly women, to be hanged, and one man crushed to death, without the slightest bit of empirical evidence?