Introduction

'All things are water.' 'You cannot step twice into the same river.' 'What is, is; what is not, is not.' 'Nothing exists but atoms and the void.' These first sentences of Western philosophy come from the thinkers before Socrates. They were the first to try to explain the whole world by a single principle, and they posed the fundamental questions of change and permanence, the one and the many, mind and matter. This volume gathers the principal fragments of Thales, Anaximander, Heraclitus, Parmenides, Zeno, Empedocles, Anaxagoras, Democritus and others, with commentary.