Laplace's demon created a Satanic scare that set the science of nonlinear dynamics back a century and a half. It was a chimera. The demon did not exist. But physicists chased the dream, and historians chased the physicists. Then the physicists created a new language, and historians learned to decipher the words. But the words spoke an ancient language already known by the historians, and through a chaotic fog the physicists could hear Clio, the muse of history ask Urania, the muse of astronomy: Is not the apparent chaos of history the fog through which we squint to make out a faint outline of meaning to chart our course from the past to the future?