Damon, son of Damonides, of the Athenian deme of Oē (sometimes spelled "Oa"), was an advisor of Pericles.
Music
Damon's expertise was supposed to be musicology, though some believed this was a cover for a broader influence over Pericles' political policy. For instance, Damon is said to have been responsible for advising Pericles to institute the policy of paying jurors for their service; this policy was widely criticized, and Damon is said to have been ostracized for it (see the Aristotelian Athenaion Poleteia), probably sometime in last third of the 5th century BCE. Plato invokes Damon many times in the Republic as the musical expert to be deferred to concerning the details of musical education. In Plato's Laches, Damon is said to have been a student of Prodicus and of Agathocles. The former was an unabashed sophist, while the latter is said (in Plato's Protagoras) to have used musical expertise as a front for being a sophist.
Damonides
The extant texts of the Aristotelian Athenaion Poleteia mention Damonides as an advisor to Pericles. The mention there of "Damonides" is now almost universally considered an editorial slip of pen, where the original text read "Damon, son of Damonides" instead (P. Rhodes, 1981, Commentary on the Aristotelian "Athenaion Politeia", p. 341). This seems to be confirmed by ostraka that have been recovered and that bear the name "Damon son of Damonides".
References
A. J. Podlecki, 1997, Perikles and His Circle, Routledge.
