In Greek mythology Cassandra foresaw calamities, but was cursed by the gods to be ignored. Modern-day Cassandras clearly predicted the disasters of Katrina, Fukushima, the Great Recession, the rise of ISIS, and many others. Like her, they were ignored. There are others right now warning of impending disasters, but how do we know which warnings are likely to be right? Through riveting explorations in a variety of fields, the authors uncover a method to separate the accurate Cassandras from the crazy doomsayers.