James Adam, The Republic of Plato

ἑρμηνεῖαι=‘communications,’ not ‘interpretations,’ as D. and V. translate. αἴσθησις is as it were the ἑρμηνεὺς καὶ ἄγγελος (Crat. 407 E） between the object of the perception and the soul: cf. παραγγέλλει in A.

λογισμόν. See on λογιστικῷ 525 B.

οὐκοῦν ἐὰν κτλ. Thus: Perception reports ‘This finger’ (let us say) ‘is big-and-little.’ Thereupon the soul is puzzled (ἀπορεῖ), and calls in νόησις. If big-and-little appear (viz. to νόησις) not one but two, then each of them appears distinct from the other, and one: cf. V 476 A and Parm. 143 D. ‘Accordingly—if each appears one, and both together two—νόησις, conceiving as it does of two (τά γε δύο), will conceive of them as separate; for otherwise it would have conceived, not of two, but of one.’ Plato's object is to make out that νόησις, in order to clear up the συγκεχυμένον τι of sensation (διὰ τὴν τούτου σαφήνειαν) is compelled to view sensation's μέγα-καὶσμικρόν (for example) separately, i.e. as τὸ μέγα and τὸ σμικρόν. These antinomies consequently force us to ask ‘What is the great?’ ‘What is the small?’ etc.; and just herein consists their periagogic or educative value, for to such questions the theory of Ideas alone furnishes an adequate and final answer (Phaed. 99 B ff.). κεχωρισμένα νοήσει perhaps=‘are separate to νόησις,’ but the ordinary view, which understands νόησις as subject to νοήσει, is better. It may have been this passage of the Republic, or Phaed. 96 E ff., or both which inspired the line of Theopompus τὰ δὲ δύο μόλις (sic) ἕν ἐστιν, ὥς φησιν Πλάτων (D. L. III 26).