Plutarch, Fr. 186 (Isidorus of Pelusium, Letters, ii. 42)
“According to Plutarch, real Atticism is a clear and straight-forward style—for, he says, their politicians spoke in this way. Gorgias of Leonini first inserted that disease into public speeches, by polishing them with elevated language and poetic devices and muddying up their clarity. This very sickness—Plutarch says—afflicted even the wondrous Plato.”
Πλουτάρχῳ δὲ δοκεῖ τὸ σαφὲς καὶ λιτὸν γνήσιον εἶναι Ἀττικισμόν· οὕτω γάρ, φησίν, ἐλάλησαν οἱ ῥήτορες. Γοργίας δ᾿ ὁ Λεοντῖνος πρῶτος τὴν νόσον ταύτην εἰς τοὺς πολιτικοὺς λόγους εἰσήγαγε τὸ ὑψηλὸν καὶ τροπικὸν ἀσπασάμενος καὶ τῇ σαφηνείᾳ λυμηνάμενος. ἥψατό τε, φησίν, ἡ νόσος αὕτη καὶ τοῦ θαυμαστοῦ Πλάτωνος.
Fr. 197 (Prolegomenon in Hermogenis περὶ στάσεων Appendices)
Ἐκ τῶν Πλουτάρχου εἰς τὸν Πλάτωνος Γοργίαν·
From Plutarch’s Commentary on Plato’s Gorgias
The field of rhetoric according to Gorgias: Rhetoric is the art which has power over speeches—it is an instrument of public persuasion in political speeches about any idea which is targeted, it is about belief and not about teaching. [Gorgias] says that its particular concern [should be] just and unjust matters, noble and ignoble, beautiful and shameful affairs.”
Ὅρος ῥητορικῆς κατὰ Γοργιάν· ῥητορική ἐστι τέχνη περὶ λόγους τὸ κῦρος ἔχουσα, πειθοῦς δημιουργὸς ἐν πολιτικοῖς λόγοις περὶ παντὸς τοῦ προτεθέντος πιστευτικῆς καὶ οὐ διδασκαλικῆς· εἶναι δὲ αὐτῆς τὴν πραγματείαν ἰδίαν μάλιστα περὶ δίκαια καὶ ἄδικα ἀγαθά τε καὶ κακὰ καλά τε καὶ αἰσχρά.