When we remember the literature of the Age of Reason, we think of satires and essays debunking the extravagance of the imagination, or of projects for improving the material conditions of mankind. We do not think of the tale of terror. Of course not! The leaders of the Enlightenment wanted to dispel the darkness where monsters live, not thicken it—not magnify it. In fact (and this is not generally known) the editors of the first Encyclopaedia even took the bold step of engaging an intrepid young rationalist to investigate outbreaks of superstition, and to expose the machinery of charlatanism or the delusions of ignorance that inspired them. His first assignment: to get to the bottom of a ridiculous report that a giant blood-sucking spider has been preying on the inhabitants of a remotevillage in the Black Forest. Utter nonsense, of course…