Since its publication in 1994, Richard McKirahan's Philosophy Before Socrates has become the standard sourcebook in Presocratic philosophy. It provides a wide survey of Greek science, metaphysics, and moral and political philosophy, from their roots in myth to the philosophers and Sophists of the fifth century. A comprehensive selection of fragments and testimonia, translated by the author, is presented in the context of a thorough and accessible discussion. An introductory chapter deals with the sources of Presocratic and Sophistic texts and the special problems of interpretation they present. In its second edition, this work has been updated and expanded to reflect important new discoveries and the most recent scholarship. Changes and additions have been made throughout, the most significant of which are found in the chapters on the Pythagoreans, Parmenides, Zeno, Anaxagoras, and Empedocles, and the new chapter on Philolaus. The translations of some passages have been revised, as have some interpretations and discussions. A new Appendix provides translations of three Hippocratic writings and the Derveni papyrus.