Evolution, Anaximander's conception of, 12; Xenophanes' theory of, 33; relation of, to fundamental conception of Being, ib.; view of Empedocles, 70

Existence, an idea prior to Time and Space, 37; not given by Experience, 45; four forms of, 166; philosophy treats of existence as such, 181

Exoteric kind of lectures, 175

Female, see Male

Fire, original of things, 17; one of two principles, 38

Flux, of all things, 16; of life, 27, 73; sophistic theory of, 87

Form v. Matter, 25, 48; Aristotle's theory of, 203

Formulae, never adequate, 122

Freewill, problem of, 33; relation to law, 113; and overruling providence, 155

Friendship, treated of in Lysis, 136