§7.525εἰ δʼ ἀεί τι αὐτῷ ἅμα ὁρᾶται ἐναντίωμα, ὥστε μηδὲν μᾶλλον ἓν ἢ καὶ τοὐναντίον φαίνεσθαι, τοῦ ἐπικρινοῦντος δὴ δέοι ἂν ἤδη καὶ ἀναγκάζοιτʼ ἂν ἐν αὐτῷ ψυχὴ ἀπορεῖν καὶ ζητεῖν, κινοῦσα ἐν ἑαυτῇ τὴν ἔννοιαν, καὶ ἀνερωτᾶν τί ποτέ ἐστιν αὐτὸ τὸ ἕν, καὶ οὕτω τῶν ἀγωγῶν ἂν εἴη καὶ μεταστρεπτικῶν ἐπὶ τὴν τοῦ ὄντος θέαν ἡ περὶ τὸ ἓν μάθησις. ἀλλὰ μέντοι, ἔφη, τοῦτό γʼ ἔχει οὐχ ἥκιστα ἡ περὶ αὐτὸ ὄψις· ἅμα γὰρ ταὐτὸν ὡς ἕν τε ὁρῶμεν καὶ ὡς ἄπειρα τὸ πλῆθος. οὐκοῦν εἴπερ τὸ ἕν, ἦν δʼ ἐγώ, καὶ σύμπας ἀριθμὸς ταὐτὸν πέπονθε τοῦτο; πῶς δʼ οὔ; ἀλλὰ μὴν λογιστική τε καὶ ἀριθμητικὴ περὶ ἀριθμὸν πᾶσα. καὶ μάλα. ταῦτα δέ γε φαίνεται ἀγωγὰ πρὸς ἀλήθειαν. ὑπερφυῶς μὲν οὖν. ὧν ζητοῦμεν ἄρα, ὡς ἔοικε, μαθημάτων ἂν εἴη· πολεμικῷ μὲν γὰρ διὰ τὰς τάξεις ἀναγκαῖον μαθεῖν ταῦτα, φιλοσόφῳ δὲ διὰ τὸ τῆς οὐσίας ἁπτέον εἶναι γενέσεως ἐξαναδύντι, ἢ μηδέποτε λογιστικῷ γενέσθαι.
"But if some contradiction is always seen at the same time in the one itself, so that it appears to be no more one than also its contrary, then there would already be need of something to judge, and the soul would be compelled in this very situation to be at a loss and to seek, stirring the thought within itself, and to ask in addition what the one itself is, and thus the study concerning the one would be among those things that lead and turn the soul around toward the contemplation of reality." "Indeed," he said, "the sight concerning the one itself has this quality in no small degree; for we see the same thing at the same time both as one and as infinite in multitude." "Therefore, if the one," I said, "is so affected, does not also all number suffer this same thing?" "How could it not?" "But indeed, calculation and arithmetic are entirely about number." "And very much so." "And these indeed appear to be leading toward truth." "Prodigiously so." "Consequently, they would belong, as it seems, to the studies we are seeking; for to a warrior it is necessary to learn these because of military ranks, and to a philosopher because he must grasp reality rising up out of generation, or else never become capable of calculation." "That is so," he said.
ἔστι ταῦτʼ, ἔφη. ὁ δέ γε ἡμέτερος φύλαξ πολεμικός τε καὶ φιλόσοφος τυγχάνει ὤν. τί μήν; προσῆκον δὴ τὸ μάθημα ἂν εἴη, ὦ Γλαύκων, νομοθετῆσαι καὶ πείθειν τοὺς μέλλοντας ἐν τῇ πόλει τῶν μεγίστων μεθέξειν ἐπὶ λογιστικὴν ἰέναι καὶ ἀνθάπτεσθαι αὐτῆς μὴ ἰδιωτικῶς, ἀλλʼ ἕως ἂν ἐπὶ θέαν τῆς τῶν ἀριθμῶν φύσεως ἀφίκωνται τῇ νοήσει αὐτῇ, οὐκ ὠνῆς οὐδὲ πράσεως χάριν ὡς ἐμπόρους ἢ καπήλους μελετῶντας, ἀλλʼ ἕνεκα πολέμου τε καὶ αὐτῆς τῆς ψυχῆς ῥᾳστώνης μεταστροφῆς ἀπὸ γενέσεως ἐπʼ ἀλήθειάν τε καὶ οὐσίαν. κάλλιστʼ, ἔφη, λέγεις.
"And our guardian happens to be both a warrior and a philosopher." "Of course." "It would be fitting then, Glaucon, to legislate this study and to persuade those who are going to participate in the greatest offices in the city to go to calculation and to apply themselves to it not in a private capacity, but until they arrive at the contemplation of the nature of numbers by intellection itself, not for the sake of buying and selling, practicing like merchants or retail-dealers, but for the sake of war and for the ease of the soul's turnabout from generation toward truth and reality." "You speak most beautifully," he said.
καὶ μήν, ἦν δʼ ἐγώ, νῦν καὶ ἐννοῶ, ῥηθέντος τοῦ περὶ τοὺς λογισμοὺς μαθήματος, ὡς κομψόν ἐστι καὶ πολλαχῇ χρήσιμον ἡμῖν πρὸς ὃ βουλόμεθα, ἐὰν τοῦ γνωρίζειν ἕνεκά τις αὐτὸ ἐπιτηδεύῃ ἀλλὰ μὴ τοῦ καπηλεύειν. πῇ δή; ἔφη.
"And indeed," I said, "now that the study concerning calculation has been mentioned, I also perceive how elegant it is and useful to us in many ways for what we want, if someone pursues it for the sake of knowing and not for the sake of retailing." "In what way indeed?" he said.
τοῦτό γε, ὃ νυνδὴ ἐλέγομεν, ὡς σφόδρα ἄνω ποι ἄγει τὴν ψυχὴν καὶ περὶ αὐτῶν τῶν ἀριθμῶν ἀναγκάζει διαλέγεσθαι, οὐδαμῇ ἀποδεχόμενον ἐάν τις αὐτῇ ὁρατὰ ἢ ἁπτὰ σώματα ἔχοντας ἀριθμοὺς προτεινόμενος διαλέγηται.
"In this very way which we were just now saying, that it leads the soul very strongly somewhere upward and compels it to discuss numbers themselves, in no way accepting it if someone discusses them by offering to it numbers having visible or tangible bodies.
οἶσθα γάρ που τοὺς περὶ ταῦτα δεινοὺς αὖ ὡς, ἐάν τις αὐτὸ τὸ ἓν ἐπιχειρῇ τῷ λόγῳ τέμνειν, καταγελῶσί τε καὶ οὐκ ἀποδέχονται, ἀλλʼ ἐὰν σὺ κερματίζῃς αὐτό, ἐκεῖνοι πολλαπλασιοῦσιν, εὐλαβούμενοι μή ποτε φανῇ τὸ ἓν μὴ ἓν ἀλλὰ πολλὰ μόρια. ἀληθέστατα, ἔφη, λέγεις.
For you surely know how those clever in these things, if someone attempts in argument to divide the one itself, laugh and do not accept it, but if you chop it up, they multiply it, taking care lest the one should ever appear not as one but as many parts." "You speak most truly," he said.