James Adam, The Republic of Plato

μάλιστα μὲν κτλ. A profounder and truly Platonic form of Hesiod's famous saying οὗτος μὲν πανάριστος ὃς αὐτὸς πάντα νοήσῃ, | ἐσθλὸς δ᾽ αὖ κἀκεῖνος ὃς εὖ εἰπόντι πίθηται (OD. 293 f., as quoted by Arist. Eth. Nic. I 2. 1095^{b} 10). Instead of οἰκεῖον ἔχοντος ἐν αὑτῷ Madvig proposes to read οἰκείου ἐνόντος ἐν αὐτῷ. The emendation is neat and gets rid of the difficulty both in ἔχοντος and in ἐφεστῶτος: but ἔχοντος ἐν αὑτῷ appropriately recalls ἔχοντος ἐν αὑτῷ above, and the genitive absolute may be compared with ἀποκριναμένου VII 538 D, ἑπομένων 586 D and δοκιμασθέντων Laws 755 D. (Badham's δοκιμασθέντας is of course only a conjecture.) Cf. Riddell Digest § 274.

ἐφεστῶτος is another independent genitive absolute. The double peculiarity is certainly unusual. Stephanus obliterates first one, and then both by suggesting (1) ἐφεστῶτα, and (2) ἔχοντι— ἐφεστώς (intended, I suppose, as neuter, but the neuter should be ἐφεστός: see Schanz Vol. II p. XII). I believe the text is sound: there is hardly any limit— except that required by intelligibility—to Plato's rapid changes of construction, and they are especially common with participles. See VI 488 D note with Engelhardt Anac. Pl. Spec. III p. 45.