In the bolded section, Socrates/Plato seems to be quoting a short part of a lecture. The effect comes across to me as a bit comedic, like he's poking fun at the idea of rhythm being capable of all this, but that would not fit with the rest of the discussion. So I think that he really is summarizing a lecture that he doesn't want to discuss in detail, and is affecting an unlikely ignorance of the subject.ἴθι δή, ἔφην, καὶ τὰ λοιπὰ καθαίρωμεν. ἑπόμενον γὰρ δὴ ταῖς ἁρμονίαις ἂν ἡμῖν εἴη τὸ περὶ ῥυθμούς, μὴ ποικίλους αὐτοὺς διώκειν μηδὲ παντοδαπὰς βάσεις, ἀλλὰ βίου ῥυθμοὺς ἰδεῖν κοσμίου τε καὶ ἀνδρείου τίνες εἰσίν: οὓς ἰδόντα τὸν πόδα τῷ τοῦ τοιούτου λόγῳ ἀναγκάζειν ἕπεσθαι καὶ τὸ μέλος, ἀλλὰ μὴ λόγον ποδί τε καὶ μέλει. οἵτινες δ᾽ ἂν εἶεν οὗτοι οἱ ῥυθμοί, σὸν ἔργον, ὥσπερ τὰς ἁρμονίας, φράσαι. ἀλλὰ μὰ Δί᾽, ἔφη, οὐκ ἔχω λέγειν. ὅτι μὲν γὰρ τρί᾽ ἄττα ἐστὶν εἴδη ἐξ ὧν αἱ βάσεις πλέκονται, ὥσπερ ἐν τοῖς φθόγγοις τέτταρα, ὅθεν αἱ πᾶσαι ἁρμονίαι, τεθεαμένος ἂν εἴποιμι: ποῖα δὲ ὁποίου βίου μιμήματα, λέγειν οὐκ ἔχω. ἀλλὰ ταῦτα μέν, ἦν δ᾽ ἐγώ, καὶ μετὰ Δάμωνος βουλευσόμεθα, τίνες τε ἀνελευθερίας καὶ ὕβρεως ἢ μανίας καὶ ἄλλης κακίας πρέπουσαι βάσεις, καὶ τίνας τοῖς ἐναντίοις λειπτέον ῥυθμούς: οἶμαι δέ με ἀκηκοέναι οὐ σαφῶς ἐνόπλιόν τέ τινα ὀνομάζοντος αὐτοῦ σύνθετον καὶ δάκτυλον καὶ ἡρῷόν γε, οὐκ οἶδα ὅπως διακοσμοῦντος καὶ ἴσον ἄνω καὶ κάτω τιθέντος, εἰς βραχύ τε καὶ μακρὸν γιγνόμενον, καί, ὡς ἐγὼ οἶμαι, ἴαμβον καί τιν᾽ ἄλλον τροχαῖον ὠνόμαζε, μήκη δὲ καὶ βραχύτητας προσῆπτε. καὶ τούτων τισὶν οἶμαι τὰς ἀγωγὰς τοῦ ποδὸς αὐτὸν οὐχ ἧττον ψέγειν τε καὶ ἐπαινεῖν ἢ τοὺς ῥυθμοὺς αὐτούς—ἤτοι συναμφότερόν τι: οὐ γὰρ ἔχω λέγειν —ἀλλὰ ταῦτα μέν, ὥσπερ εἶπον, εἰς Δάμωνα ἀναβεβλήσθω: διελέσθαι γὰρ οὐ σμικροῦ λόγου.
Adam and Jowett have different views of this.
Adam's notes
"καὶ ἴσον ἄνω καὶ κάτω τιθέντος" - Is Adam correct about what's going on here?
Where does Adam's description of the ἐνόπλιος (x _ u u _ u u _) come from? Is J&C's simpler cretic explanation at all realistic?