Glaucon
From LSJ
Ἀμήχανον δὲ παντὸς ἀνδρὸς ἐκμαθεῖν ψυχήν τε καὶ φρόνημα καὶ γνώμην πρὶν ἂν ἀρχαῖς τε καὶ νόμοισιν ἐντριβὴς φανῇ → It is impossible to know the spirit, thought, and mind of any man before he be versed in sovereignty and the laws
Ἀμήχανον δὲ παντὸς ἀνδρὸς ἐκμαθεῖν ψυχήν τε καὶ φρόνημα καὶ γνώμην πρὶν ἂν ἀρχαῖς τε καὶ νόμοισιν ἐντριβὴς φανῇ → It is impossible to know the spirit, thought, and mind of any man before he be versed in sovereignty and the laws