This is an investigation of Aristotle's conception of accidental compounds (or "kooky objects," as Gareth Matthews has called them)—entities such as the pale man and the musical man. I begin with Matthews's pioneering work into kooky objects, and argue that they are not so far removed from our ordinary thinking as is commonly supposed. I go on to assess their utility in solving some familiar puzzles involving substitutivity in epistemic contexts, and compare the kooky object approach to more modern approaches (...) involving the notion of referential opacity. I conclude by proposing that Aristotle provides an implicit role for kooky objects in such metaphysical contexts as the Categories and Metaphysics. (shrink)