ἀδυναμία τοῦ ἀδικεῖν

From LSJ

μεγάλα ὠφελήσεσθε πρὸς ἱστορίαν τῶν κοινῶν → that will be of great benefit to you in order to understand public affairs

Source

Greek > English (Woodhouse)

inability to do wrong, powerlessness to do wrong