In every domain of reasoning-from time and space, to mental states and physical illness-humans deploy an exceedingly diverse range of intuitive 'theories' about how the world works. Children from diverse cultures always seem to arrive at a few, common folk theories as they hone their developing brains against roughly similar interactions with people and objects. The result is an impressive panoply of folk notions that the human species uses to explain, predict, and just plain talk about everything from why the sky is blue, to why we catch a cold when we stand out in the rain. Unquestionably,...