The witch, the vampire and the werewolf endure as popular characters in modern horror. These "old monsters" have their origins in the writings of Aristotle as studied in the universities of medieval Europe, where 13th-century scholars reconciled works of natural philosophy and medicine with theological precepts. They codified divine perfection as warm, light, male and associated with the ethereal world beyond the moon, while evil imperfection was cold, dark, female and bound to the corrupt world below the moon. All who did not conform to divine goodness--including un-holy women and Jews--were...