Plato, Letters 313d

παρὰ τὰ τῶν ἄλλων καὶ αὐτὰ καθʼ αὑτά, νῦν σοι ταῦτά τε, εἰ ἀληθὴς ἡ βάσανος, προσφύσεται, καὶ οἰκεῖος τούτοις τε καὶ ἡμῖν ἔσῃ. πῶς οὖν αὐτά τʼ ἔσται καὶ πάντα ἃ εἰρήκαμεν; τὸν Ἀρχέδημον νῦν τε ὀρθῶς ἐποίησας πέμψας, καὶ τὸ λοιπόν, ἐπειδὰν ἔλθῃ πρὸς σὲ καὶ ἀπαγγείλῃ τὰ παρʼ ἐμοῦ, μετὰ ταῦτα ἴσως ἄλλαι σε ἀπορίαι λήψονται. πέμψεις οὖν αὖθις, ἂν ὀρθῶς βουλεύῃ, παρʼ ἐμὲ τὸν Ἀρχέδημον, ὁ δʼ ἐμπορευσάμενος ἥξει πάλιν· καὶ τοῦτο ἐὰν δὶς ἢ τρὶς ποιήσῃς καὶ

by examining my teaching side by side with theirs, as well as by itself, then, if the test you make is a true one, not only will these doctrines implant themselves now in your mind, but you also will be devoted both to them and to us. How, then, will this, and all that I have said, be brought to pass? You have done right now in sending Archedemus; and in the future also, after he returns to you and reports my answer, you will probably be beset later on with fresh perplexities. Then, if you are rightly advised, you will send Archedemus back to me, and he with his cargo will return to you again.