Plato, Letters 337b

πόλις ἐν αὑτῇ στασιάσασα, ἀλλὰ στάσεις καὶ ἔχθραι καὶ μίση καὶ ἀπιστίαι ταῖς οὕτω διατεθείσαις πόλεσιν αὐταῖς πρὸς αὑτὰς ἀεὶ γίγνεσθαι φιλεῖ. τοὺς δὴ κρατήσαντας ἀεὶ χρή, ὅτανπερ ἐπιθυμήσωσιν σωτηρίας, αὐτοὺς ἐν αὑτοῖς ἄνδρας προκρῖναι τῶν Ἑλλήνων οὓς ἂν πυνθάνωνται ἀρίστους ὄντας, πρῶτον μὲν γέροντας, καὶ παῖδας καὶ γυναῖκας κεκτημένους οἴκοι καὶ προγόνους αὑτῶν ὅτι μάλιστα πολλούς τε καὶ ἀγαθοὺς καὶ ὀνομαστοὺς καὶ κτῆσιν κεκτημένους πάντας

strife and enmity and hatred and suspicion are wont to keep for ever recurring in cities when their inner state is of this kind. Now those who have gained the mastery, whenever they become desirous of safety, ought always to choose out among themselves such men of Greek origin as they know by inquiry to be most excellent—men who are, in the first place, old, and who have wives and children at home, and forefathers as numerous and good and famous as possible, and who are all in