The history of philosophy can be divided in many ways. One illuminating story sees that history as a series of dialectical "turns" — the "ontological turn" institutionalized by Plato, the "theological turn" inaugurated by the Mediaeval Christian rediscovery of Aristotle, the "epistemological turn—" initated by Descartes, and the "logico-linguistic" turn executed at the beginning of this century by Frege, Husserl, Wittgenstein, and Russell. What is, perhaps, a more fundamental story, however, sees even these dialectical turns as mere moments in the interweaving flow of two great streams — the first springing from the wellhead of Plato, the second from Aristotle.