Abstract
Under 336/5 Diodorus records: Of such a Common Peace prompted by Persia Xenophon gives no hint. After recording the failure of the Theban attempt to summon a Congress at Thebes to swear a peace on the basis of the terms negotiated by Pelopidas at Susa, he goes on to record negotiations where by certain allies of Sparta made peace with Thebes, but his account contains no mention of either Persia or Athens. To his narrative the Archidamus of Isocrates seems to fit. The imagined scene of the speech is the last meeting of the Peloponnesian League; Corinth, Phlius, and Epidaurus are seeking Sparta's permission for them to make peace with Thebes, the very situation that Xenophon speaks of, and, at first sight, it seems that only those cities are involved. There is thus a serious conflict in the evidence, and for over half a century scholars have been unable to agree as to which account to choose. Most have declared in favour of Diodorus, primarily on the ground that his source is more trustworthy than Xenophon, but some remain sceptical and the subject has recently been re-examined by Ryder, who has concluded that, where Xenophon is so full and precise, there is no justification for preferring the brief notice of Diodorus. A resolution of this question would be of great assistance to understanding the 360's, and it is the purpose of this article to advance considerations in support of Diodorus.