Plato, "The Seventh Letter"
J. Harward (trans.), Plato: The Seventh Letter1
Plato, Epistle VII, 344b-c:
After much effort, as names, definitions, sights, and other data of sense, are brought into contact and friction one with another, in the course of scrutiny and kindly testing by men who proceed by question and answer without ill will, with a sudden flash there shines forth understanding about every problem, and an intelligence whose efforts reach the furthest limits of human powers.
John Burnet (ed.), Platonis Opera, Vol. V, Pt. II: Tetralogia IX Definitiones et Spuria continens, Oxford Classical Texts, Clarendon Press, 19072
Plato, Epistle VII, 344b-c:
μόγις δὲ τριβόμενα πρὸς ἄλληλα αὐτῶν ἕκαστα, ὀνόματα καὶ λόγοι ὄψεις τε καὶ αἰσθήσεις, ἐν εὐμενέσιν ἐλέγχοις ἐλεγχόμενα καὶ ἄνευ φθόνων ἐρωτήσεσιν καὶ ἀποκρίσεσιν χρωμένων, ἐξέλαμψε φρόνησις περὶ ἕκαστον καὶ νοῦς, συντείνων ὅτι μάλιστʼ εἰς δύναμιν ἀνθρωπίνην.