Aelian, Varia Historia 2.30
“Plato, the son of Ariston, at first pursued poetry and used to write heroic verse. But he soon burned it all because he despised it, since he reckoned that his poetry was far inferior when compared to Homer’s. He then tried tragedy and even completed a tetralogy, and he was about to enter the competition, even to the point of giving the verses to actors. But right before the Dionysia, he went and heard Socrates; and once he was seized by that Siren, he not only withdrew from the competition, but he also gave up the writing of tragedy for good to immerse himself in philosophy.”
Πλάτων ὁ ᾿Αρίστωνος τὰ πρῶτα ἐπὶ ποιητικὴν ὥρμησε, καὶ ἡρωϊκὰ ἔγραφε μέτρα• εἶτα αὐτὰ κατέπρησεν ὑπεριδὼν αὐτῶν, ἐπεὶ τοῖς ῾Ομήρου αὐτὰ ἀντικρίνων ἑώρα κατὰ πολὺ ἡττώμενα. ἐπέθετο οὖν τραγῳδίᾳ, καὶ δὴ καὶ τετραλογίαν εἰργάσατο, καὶ ἔμελλεν ἀγωνιεῖσθαι, δοὺς ἤδη τοῖς ὑποκριταῖς τὰ ποιήματα. πρὸ τῶν Διονυσίων δὲ παρελθὼν ἤκουσε Σωκράτους, καὶ ἅπαξ αἱρεθεὶς ὑπὸ τῆς ἐκείνου σειρῆνος, τοῦ ἀγωνίσματος οὐ μόνον ἀπέστη τότε, ἀλλὰ καὶ τελέως τὸ γράφειν τραγῳδίαν ἀπέρριψε, καὶ ἀπεδύσατο ἐπὶ φιλοσοφίαν.