T. G. Tucker, Commentary on Thucydides: Book 8

αὐτοί θ᾽ ἑαυτοῖς These words go closely with ἐλπίδας εἶχον, while ἐς ἑαυτοὺς is part of a phrase with περιποήσειν. Moreover, αὐτοί θ᾽ ἑαυτοῖς is in contrast with καὶ τῶν πολεμίων . . . Thus we have no mere pleonasm: ‘they entertained great hopes both for themselves personally (to wit that they would get the control of affairs into their own hands), and also that they would overcome the enemy.’ There was in this new proposal a double chance (1) to get power for themselves, (2) to crush the Peloponnesians.

οἵπερ καὶ ταλαιπωροῦνται μάλιστα, the relative clause in the present tense to express a general truth. In point of position the clause might have been expected to come immediately after πολιτῶν; but it is not merely descriptive or attributive, and is put after τὰ πράγματα for the reason that the antithesis is between powers and burdens: ‘they hoped to get the greatest powers just as they bore the greatest burdens.’ The greater burdens of the aristocrats are alluded to in the same terms, c. 63, § 4, ἐσφέρειν ἐκ τῶν ἰδίων οἴκων προθύμως χρήματα, ὡς οὐκέτι ἄλλοις ἢ σφίσιν αὐτοῖς ταλαιπωροῦντας. The δυνατοὶ are of course the rich, as οἱ ἀσθενεῖς are the poor in Xen. Cyr. viii. 1, 30; Eur. Suppl. 434, etc.

περιποήσειν The active because of the reflexive expressed (ἐς ἑαυτοὺς). Cf. Isaeus, 64, 6, πάντα εἰς αὑτὸν περιεπόησε. Without the reflexive the middle occurs in i. 9, δύναμιν περιποησάμενος; i. 15, ἰσχὺν περιεποήσαντο. In other writers, however, the middle and reflexive are combined often enough, e.g. Xen. Anab. v. 6, 17.