 The basic building blocks of reality, (Aristotelian) science tells us, are particular matter-form compounds. Yet science’s own starting-points are the forms—the universal essences—of such things. There is no science of you, or of me, though there is one of human beings. How, then, can science possibly be reflecting accurately the structure of reality, when its starting-points and those of reality fail so radically to map onto each other? For there is no greater difference, it seems, than that between particulars and universals. The thing to do, then, given that science provides our best access to the nature of reality, is to investigate the universal forms or essences that are basic to it.