This work is a collection and discussion of the primary sources for Hellenistic philosophy. By presenting the material both in its original languages and in translation, we aim to give classicists and philosophers direct access to the surviving evidence on the Stoics, Epicureans, Pyrrhonists and Academics, whose thought dominated philosophy in the three centuries after the death of Aristotle in 322 b.c. There has been a remarkable upsurge of interest in these philosophies over the last few decades, but up to now the original texts have not been collected in any single book with the comprehensiveness and detail we have sought to provide.

In its scope and purpose our book closely resembles G. S. Kirk, J. E. Raven, and M. Schofield, The Presocratic Philosophers (ed. 2, 1983), but we divide the material between two volumes. Vol. 1 is entirely in English, offering translations of texts, accompanied by philosophical commentary. It is presented in a manner which we hope will make it usable by those with no historical background in the classical world. With its glossary and set of indexes, it is designed to be entirely self-sufficient. But the expectation is that our classical readers will use it in conjunction with vol. 2. This latter supplies (sometimes in longer excerpts) the texts translated in vol. 1, together with critical apparatus, information on their original contexts, supplementary commentary on technical matters and points of detail, and some additional texts.