οἱ ὠνούμενοι: sc. ἀγνοοῖεν ἄν.
τυγχάνεις ἐπιστήμων: Plato rarely uses τυγχάνειν without a partic. Cf. Phaedr. 230 a εἴτε τι θηρίον τυγχάνω Τυφῶνος πολυπλοκώτερον (more complex), Rep. ii. 369 b ἐπειδὴ τυγχάνει ἡμῶν ἕκαστος οὐκ αὐτάρκης, ἀλλὰ πολλῶν ἐνδεής since no one of us is self-sufficing, but each has many wants, Tim. 61 c τυγχάνει δὲ οὔτε ταῦτα οὔτ᾽ ἐκεῖνα δυνατὰ ἱκανῶς λεχθῆναι.