J. Adam, A. M. Adam, Commentary on Plato, Protagoras
J. Adam & A. M. Adam, Ed.

23. αὐτό σε διδάξει: ‘fact will show you,: Theaet. 200E ὁ τὸν ποταμὸν καθηγούμενος—ἔφη ἄρα δείξειν αὐτό; the idiom is a frequent one.

25. οὐδεὶς γάρ κολάζει κτλ. Plato's own theory of punishment so far agrees with this, but goes deeper: see Gorg. 525A ff. προσήκει δὲ παντὶ τῷ ἐν τιμωρίᾳ ὄντι, ὑπ᾽ ἄλλου ὀρθῶς τιμωρουμένῳ, ἢ βελτίονι γίγνεσθαι καὶ ὀνίνασθαι ἢ ραπαδείγματι τοῖς ἄλλοις γίγνεσθαι, ἵνα ἄλλοι ὁρῶντες πάσχοντα ἃ ἂν πάσχῃ φοβούμενοι βελτίους γίγνωνται. Vice (being ignorance) is disease of soul, as νόσος is of body: it is the business of the judge to cure the one as of the physician to cure the other: cf. Rep. IX. 591A-B and Gorg. 478D σωφρονίζει γάρ που καὶ δικαιοτέρους ποιεῖ καὶ ἰατρικὴ γίγνεται πονηρίας ἡ δίκη: hence (ibid. 480B ff.) the sinner should go before the judge as readily as the patient to a doctor, and should even accuse his friends. In the ideal city the judges are to put to death incurable sinners just as the doctors will allow incurable patients to die: Rep. III. 409E ff. τῶν πολιτῶν σοι τοὺς μὲν εὐφυεῖς τὰ σώματα καὶ τὰς ψυχὰς θεπαρεύσουσι, τοὺς δὲ μή, ὅσοι μὲν κατὰ σῶμα τοιοῦτοι, ἀροθνῄσκειν ἐάσουσι, τοὺς δὲ κατὰ τὴν ψυχὴν κακοφυεῖς καὶ ἀνιάτους αὐτοὶ ἀποκτενοῦσιν. The same holds good of punishment after death: for Ardiaeus and the others in Rep. X. 616A, whose punishment is everlasting (οὐχ ἥκει—οὐδ᾽ ἂν ἥξει δεῦρο), are incurable—ἀτεχνῶς παραδείγματα ἀνηρτημένους ἐκεῖ ἐν ᾄδου ἐν τῷ δεσμωτηπίῳ, τοῖς ἀεὶ τῶν ἀδίκων ἀφικνουμένοις θεάματα καὶ νουθετήματα—the majority are punished to purge them of the guilt contracted upon earth and teach them to choose more wisely their lot of life next time. The remedial view of punishment is embedded in the genius of the Greek language, as is shown by the punitive sense of σωφρονίζειν, δικαιοῦν, εὐθύνειν. The older and sterner view (δράσαντι παθεῖν) appears more rarely in Plato's time.