The third volume of my History of Greek Philosophy (Cambridge University Press, 1969) was divided into two parts, entitled respectively ‘The World of the Sophists’ and ‘Socrates’. By issuing the two parts separately in paperback form, the Press hopes to make them more easily and cheaply available to students. This book reproduces the second part, with the minimum of alterations necessary to allow it to appear as a separate publication. Mentions of‘vol. I’ or ‘vol. II’ in the text refer to the earlier volumes of this work.

Books have most frequently been referred to in the text and notes by short titles, and articles by periodical and date only. Full particulars of books, and titles and page-references for articles, will be found in the bibliography. The fragments of the Sophists, and other texts relating to them, are included in the Fragmente der Vorsokratiker of Diels and Kranz (abbreviated DK). The texts in an ‘A’ section of DK (Testimonia) have their number preceded by this letter, and those in a ‘B’ section, purporting to be actual quotations from the philosopher in question, are designated ‘fr.’ (fragment).

Translations, from both ancient and modern authors, are my own unless otherwise stated.