Possibility

ἔδει, ἐχρῆν.—The imperfect of verbs expressing obligation or duty may refer to present time and imply that the obligation or duty is not fulfilled: σῑγήσᾱς ἡνίκ᾽ ἔδει λέγειν keeping silence when he ought to speak D. 18.189. So with ἐχρῆν it were proper, εἰκὸς ἦν it were fitting (1774). But the imperfect may also express past obligation without denying the action of the infinitive, as ἔδει μένειν he was obliged to remain (and did remain) D. 19.124, ὅπερ ἔδει δεῖξαι quod erat demonstrandum Euclid 1. 5 (1779).

Past Potential.—The past tenses (usually the aorist, less commonly the imperfect) of the indicative with ἄν (κέν) denote past potentiality, probability (cautious statement), or necessity: ὃ οὐκ ἂν ᾤοντο which they could not have expected T. 7.55, τίς γὰρ ἂν ᾠήθη ταῦτα γενέσθαι; for who would have expected these things to happen? D. 9.68 (note that ἄν does not go with γενέσθαι by 1764), ἔγνω ἄν τις one might (could, would) have known X. C. 7.1.38, ὑπό κεν ταλασίφρονά περ δέος εἷλεν fear might have seized even a man of stout heart Δ 421.

a. This is especially frequent with τὶς and with the ideal second person (cp. putares, crederes): ἐπέγνως ἄν you would (could, might) have observed X. C. 8.1.33.

b. The potential optative (1829) in Homer refers also to the past.

ἄν with the infinitive expressing possibility, and representing either a potential indicative or a potential optative, occasionally follows ὥστε (ὡς).

a. Not in indirect discourse: καί μοι οἱ θεοὶ οὕτως ἐν τοῖς ἱεροῖς ἐσήμηναν ὥστε καὶ ἰδιώτην ἂν γνῶναι (= ἰδιώτης ἔγνω ἄν or γνοίη ἄν) ὅτι τῆς μοναρχίᾱς ἀπέχεσθαί με δεῖ and the gods declared to me so clearly in the sacrifices that even a common man could understand that I must keep aloof from sovereignty X. A. 6.1.31, ἐν τῷ ἀσφαλεῖ ἤδη ἔσομαι ὡς μηδὲν ἂν ἔτι κακὸν παθεῖν ( = οὐδὲν ἂν ἔτι πάθοιμι) I shall soon be safe from suffering any further evil X. C. 8.7.27. The difference in meaning is very slight between the construction with the potential optative and that with the infinitive with ἄν representing the potential optative.

N.—Rarely in other cases. Thus, τὰ δὲ ἐντὸς οὕτως ἐκαίετο ὥστε . . . ἥδιστα ἂν ἐς ὕδωρ ψῡχρὸν σφᾶς αὐτοὺς ῥῑ́πτειν ( = ἔρρῑπτον, 2304) but their internal parts were inflamed to such a degree that they would have been most glad to throw themselves into cold water (had they been permitted) T. 2.49.

b. In indirect discourse: ἆρ᾽ οὖν δοκεῖ τῳ ῡ̔μῶν ὀλιγώρως οὕτως ἔχειν χρημάτων Νῑκόδημος ὥστε παραλιπεῖν ( = παρέλιπεν) ἄν τι τῶν τοιούτων; does it seem to any one of you that Nicodemus so despised money that he would have neglected any agreement of the sort? Is. 3.37.