§158ΘΕΑΙ. ἀληθέστατα λέγεις, ὦ Σώκρατες.
THEAETETUS: You speak most truly, Socrates.
ΣΩ. τίς δὴ οὖν, ὦ παῖ, λείπεται λόγος τῷ τὴν αἴσθησιν ἐπιστήμην τιθεμένῳ καὶ τὰ φαινόμενα ἑκάστῳ ταῦτα καὶ εἶναι τούτῳ ᾧ φαίνεται;
SOCRATES: What argument, then, my boy, is left for the one who posits that perception is knowledge, and that what appears to each person actually is for the one to whom it appears?
ΘΕΑΙ. ἐγὼ μέν, ὦ Σώκρατες, ὀκνῶ εἰπεῖν ὅτι οὐκ ἔχω τί λέγω, διότι μοι νυνδὴ ἐπέπληξας εἰπόντι αὐτό.
THEAETETUS: For my part, Socrates, I hesitate to say that I do not know what to say, because you just rebuked me for saying that.
ἐπεὶ ὡς ἀληθῶς γε οὐκ ἂν δυναίμην ἀμφισβητῆσαι ὡς οἱ μαινόμενοι ἢ ὀνειρώττοντες οὐ ψευδῆ δοξάζουσιν, ὅταν οἱ μὲν θεοὶ αὐτῶν οἴωνται εἶναι, οἱ δὲ πτηνοί τε καὶ ὡς πετόμενοι ἐν τῷ ὕπνῳ διανοῶνται.
Since indeed in real truth I should not be able to dispute that those who are mad or dreaming do not hold false beliefs, when some of them think they are gods, and others imagine they have wings and are, as it were, flying in their sleep.
ΣΩ. ἆρʼ οὖν οὐδὲ τὸ τοιόνδε ἀμφισβήτημα ἐννοεῖς περὶ αὐτῶν, μάλιστα δὲ περὶ τοῦ ὄναρ τε καὶ ὕπαρ;
SOCRATES: Do you not, then, even reflect on this sort of dispute about them, and especially about dream and waking?
ΘΕΑΙ. τὸ ποῖον;
THEAETETUS: What sort?
ΣΩ. ὃ πολλάκις σε οἶμαι ἀκηκοέναι ἐρωτώντων, τί ἄν τις ἔχοι τεκμήριον ἀποδεῖξαι, εἴ τις ἔροιτο νῦν οὕτως ἐν τῷ παρόντι πότερον καθεύδομεν καὶ πάντα ἃ διανοούμεθα ὀνειρώττομεν, ἢ ἐγρηγόραμέν τε καὶ ὕπαρ ἀλλήλοις διαλεγόμεθα.
SOCRATES: The one which I think you have often heard people asking: what proof one could show, if someone were to ask right now in the present, whether we are asleep and all that we are thinking is a dream, or whether we are awake and conversing with one another in a waking state.
ΘΕΑΙ. καὶ μήν, ὦ Σώκρατες, ἄπορόν γε ὅτῳ χρὴ ἐπιδεῖξαι τεκμηρίῳ· πάντα γὰρ ὥσπερ ἀντίστροφα τὰ αὐτὰ παρακολουθεῖ.
THEAETETUS: And indeed, Socrates, it is hard to see by what proof one ought to demonstrate it; for all the same things follow as if they were counterparts.
ἅ τε γὰρ νυνὶ διειλέγμεθα οὐδὲν κωλύει καὶ ἐν τῷ ὕπνῳ δοκεῖν ἀλλήλοις διαλέγεσθαι· καὶ ὅταν δὴ ὄναρ ὀνείρατα δοκῶμεν διηγεῖσθαι, ἄτοπος ἡ ὁμοιότης τούτων ἐκείνοις.
For nothing prevents what we have just now conversed about from seeming to be a conversation with one another in sleep as well; and indeed when in a dream we seem to relate dreams, the similarity of these to those is strange.
ΣΩ. ὁρᾷς οὖν ὅτι τό γε ἀμφισβητῆσαι οὐ χαλεπόν, ὅτε καὶ πότερόν ἐστιν ὕπαρ ἢ ὄναρ ἀμφισβητεῖται, καὶ δὴ ἴσου ὄντος τοῦ χρόνου ὃν καθεύδομεν ᾧ ἐγρηγόραμεν, ἐν ἑκατέρῳ διαμάχεται ἡμῶν ἡ ψυχὴ τὰ ἀεὶ παρόντα δόγματα παντὸς μᾶλλον εἶναι ἀληθῆ, ὥστε ἴσον μὲν χρόνον τάδε φαμὲν ὄντα εἶναι, ἴσον δὲ ἐκεῖνα, καὶ ὁμοίως ἐφʼ ἑκατέροις διισχυριζόμεθα.
SOCRATES: Do you see, then, that to dispute is not difficult, since even whether it is waking or a dream is disputed, and indeed, the time being equal which we sleep to that which we are awake, in each state our soul contends that the opinions present at the time are more than anything true, so that for an equal time we say these things are real, and for an equal time those, and we insist upon each of them similarly.
ΘΕΑΙ. παντάπασι μὲν οὖν.
THEAETETUS: Absolutely so.
ΣΩ. οὐκοῦν καὶ περὶ νόσων τε καὶ μανιῶν ὁ αὐτὸς λόγος, πλὴν τοῦ χρόνου ὅτι οὐχὶ ἴσος;
SOCRATES: Is not, then, the same argument applicable to diseases and madness, except that the time is not equal?
ΘΕΑΙ. ὀρθῶς.
THEAETETUS: Right.
ΣΩ. τί οὖν;
SOCRATES: What then?
πλήθει χρόνου καὶ ὀλιγότητι τὸ ἀληθὲς ὁρισθήσεται;
Will truth be defined by the length or shortness of time?
ΘΕΑΙ. γελοῖον μεντἂν εἴη πολλαχῇ.
THEAETETUS: That would indeed be ridiculous in many ways.
ΣΩ. ἀλλά τι ἄλλο ἔχεις σαφὲς ἐνδείξασθαι ὁποῖα τούτων τῶν δοξασμάτων ἀληθῆ;
SOCRATES: But have you any other clear way to show which of these opinions is true?
ΘΕΑΙ. οὔ μοι δοκῶ.
THEAETETUS: I do not think so.
ΣΩ. ἐμοῦ τοίνυν ἄκουε οἷα περὶ αὐτῶν ἂν λέγοιεν οἱ τὰ ἀεὶ δοκοῦντα ὁριζόμενοι τῷ δοκοῦντι εἶναι ἀληθῆ. λέγουσι δέ, ὡς ἐγὼ οἶμαι, οὕτως ἐρωτῶντες·
SOCRATES: Listen then to me as to what those who define what appears at any time to be true for the one to whom it appears would say about them.
ὦ Θεαίτητε, ὃ ἂν ἕτερον ᾖ παντάπασιν, μή πῄ τινα δύναμιν τὴν αὐτὴν ἕξει τῷ ἑτέρῳ;
And they speak, I think, by asking in this way: "Theaetetus, if something is altogether different, will it in any way have any of the same power as the other?
καὶ μὴ ὑπολάβωμεν τῇ μὲν ταὐτὸν εἶναι ὃ ἐρωτῶμεν τῇ δὲ ἕτερον, ἀλλʼ ὅλως ἕτερον.
And let us not suppose that the thing we are asking about is the same in one respect and different in another, but altogether different."