Isocrates (īsŏk´rətēz), 436–338 BC, one of the Ten Attic Orators. He was a pupil of Socrates and of the Sophists. Perhaps the greatest teacher in Greek history, he taught every younger orator of his time. He did not deliver his speeches, but either wrote for litigants (six such speeches survive) or wrote discourses to be read (15 of which remain) dealing mainly with politics and education. Panegyricus (in which he urges Hellenic unity against Persia) is his most celebrated oration. Isocrates committed suicide (according to tradition) after the defeat of Athens by Philip II of Macedon at Chaeronea.