Plato, Laws 636b

τὰ δὲ καὶ ὠφελοῦν. ἐπεὶ καὶ τὰ γυμνάσια ταῦτα καὶ τὰ συσσίτια πολλὰ μὲν ἄλλα νῦν ὠφελεῖ τὰς πόλεις, πρὸς δὲ τὰς στάσεις χαλεπά—δηλοῦσιν δὲ Μιλησίων καὶ Βοιωτῶν καὶ Θουρίων παῖδες—καὶ δὴ καὶ παλαιὸν νόμον δοκεῖ τοῦτο τὸ ἐπιτήδευμα καὶ κατὰ φύσιν, τὰς περὶ τὰ ἀφροδίσια ἡδονὰς οὐ μόνον ἀνθρώπων ἀλλὰ καὶ θηρίων, διεφθαρκέναι. καὶ τούτων τὰς ὑμετέρας πόλεις πρώτας ἄν τις αἰτιῷτο καὶ

So these common meals, for example, and these gymnasia, while they are at present beneficial to the States in many other respects, yet in the event of civil strife they prove dangerous (as is shown by the case of the youth of Miletus, Bocotia and Thurii); and, moreover, this institution, when of old standing, is thought to have corrupted the pleasures of love which are natural not to men only but also natural to beasts. For this your States are held primarily responsible, and along with them all others