Empedocles’ The Testimonia, Volume II

The invention of rhetoric, and the line of descent

Sextus Empiricus, Against the Professors

Aristotle says that Empedocles was the first to set rhetoric in motion.

Quintilian, The Orator's Education

For Empedocles is said to have been the first, after those whom the poets hand down, to have set anything moving in the matter of rhetoric. The oldest writers of handbooks were Corax and Tisias, both Sicilians, and after them came a man of the same island, Gorgias of Leontini, who is said to have been Empedocles' pupil.

Aristotle, Sophistical Refutations

Those who are held in repute today received the art from many hands, as it were by succession, each carrying it forward a little, and so have enlarged it — Tisias after the first men, Thrasymachus after Tisias.

Scholiast on Iamblichus, Life of Pythagoras

So dialectic began from Pythagoras, and rhetoric likewise; for Tisias and Gorgias and Polus were pupils of Empedocles the Pythagorean.

Four witnesses to one claim of Aristotle's.

Aristotle's claim is bare — Empedocles set rhetoric moving — and the later writers supply a genealogy to go with it: Empedocles to Gorgias, Gorgias to Athens, and from Athens everything. The scholiast pushes it one step further back, to Pythagoras, which is a Neoplatonist's tidiness rather than history. What survives the sceptics is the middle link, since Gorgias' pupilage is independently attested at A 1 § 58.

Bearing on Volume I. A 1 §§ 57–58.

Aristotle's own phrase at Sophistical Refutations 183b is "after the first men," which Diels takes to be the passage Sextus and Quintilian are summarising.