Plato, Laws 936a

ἐξείργειν ἐκ τῆς χώρας τὸ παράπαν αὐθημερόν, ἢ ζημιοῦσθαι μναῖς τρισὶν ἱεραῖς τοῦ θεοῦ οὗ ἂν ἀγὼν ᾖ. οἷς δʼ εἴρηται πρότερον ἐξουσίαν εἶναι περί του ποιεῖν, εἰς ἀλλήλους τούτοις ἄνευ θυμοῦ μὲν μετὰ παιδιᾶς ἐξέστω, σπουδῇ δὲ ἅμα καὶ θυμουμένοισιν μὴ ἐξέστω. τούτου δὴ διάγνωσις ἐπιτετράφθω τῷ τῆς παιδεύσεως ὅλης ἐπιμελητῇ τῶν νέων· καὶ ὃ μὲν ἂν οὗτος ἐγκρίνῃ, προφέρειν εἰς τὸ μέσον ἐξέστω τῷ ποιήσαντι, ὃ δʼ ἂν ἀποκρίνῃ, μήτε αὐτὸς ἐπιδεικνύσθω

shall on the same day banish him wholly from the country, failing which they shall be fined three minas, dedicated to the god whose festival is being held. Those to whom permission has been given, as we previously said, to write songs about one another shall be allowed to ridicule others in jest and without passion; but they shall not be allowed to do so with passion and in earnest. The task of making this distinction shall be entrusted to the minister in charge of the general education of the young: whatever he shall approve, the composer shall be allowed to produce in public, but whatever he shall disapprove, the composer shall be forbidden either personally to exhibit to anyone or to be found teaching to any other person, free man or slave;