Soothsayers have been around as long as recorded history, probably longer—after all, knowing what’s to come has always been accorded more value than knowing what’s already happened. Whether Isaiah shouting from the mountaintop or Jim Cramer shouting from the television screen, there has always been power and notoriety to be gained from prognostication. But considering that most (if not all) of these seers—whatever market expertise or God-given insight they might claim for themselves—are just shooting in the dark, it’s not altogether clear what makes a good prophet. Showmanship and some lucky guesses, to be sure, but beyond that? This is the question that surrounds the strange and enduring popularity of one of the unlikeliest prophets: an ex-doctor from southern France named Nostradamus.