E.C. Marchant, Commentary on Thucydides: Book 3

πάντων δ᾽ αὐτῶν αἴτιον—‘the cause of all that was office (i.e. the desire of office), resting on covetousness and ambition.’

ἐκ δ᾽ αὐτῶν—viz. πλεονεξίας καὶ φιλοτιμίας.

καθισταμένων—masc., ‘when men were settling down to.’ The καί belongs, not merely to ἐς τὸ φιλονικεῖν, but to the whole phrase to πρόθυμον.

πλήθους . . σώφρονος—these are the fine names that were used for δημοκρατία and ὀλιγαρχία. ἰσονομία was a catchword with democrats, σωφροσύνη with aristocrats.

ἆθλα—this suggests several of the words that follow— ἀγωνιζόμενοι, περιγενέσθαι, ἐπεξῇσαν (the last unusual with object)—the general idea being that of a desperate struggle between enemies. (Very like is Xen Cyr. II. 2, 18-19.)

ἔτι μείζους—as compared with the τολμήματα.

προστιθέντες—from Dionysins, in place of προτιθέντες of the MSS., for ‘to threaten’ hardly suits with what precedes.

ψήφου ἀδίκου—best taken as subjective gen. depending on καταγνώσεως.

χειρί—the contrast is between force and the forms of law.

ἐνόμιζον—with dat., as χρῆσθαι.

εὐπρεπείᾳ δὲ λόγου—since εὐσέβεια and λόγου εὐπρέπεια are not a proper contrast, many suppose that the contrast to the former is to be found in ἐπιφθόνως τι, and consequently attach εὐπρεπείᾳ δὲ λόγου to the rel. sentence, ‘those who managed to hide some malicious act under fair words.’ But the μὲν . . δέ contrast is not between single words, but between the two sentences as a whole: εὐσέβεια is ‘a name for piety,’ as e.g. in Soph. Ant. 924 τὴν δυσσέβειαν (‘reputation of being δυσσεβής’) εὐσεβοῦσ᾽ ἐκτησάμην, ‘on this pretence, covering an odious act, earned a better reputation.’ Thuc not seldom puts two similar words (εὐσέβεια—εὐπρέπεια) in contrast that do not really form an antithesis.

τὰ δὲ μέσα τῶν πολιτῶν—for the moderate element and the preference given to it by so many thinking men cf. Eur. Suppl. 244 τριῶν δὲ μοιρῶν ἡ 'ν μέσῳ σῴζει πόλεις.