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σφαλερὰ πρὸς ὑγίειαν ἕξις

From LSJ

Ἔοικα γοῦν τούτου γε σμικρῷ τινι αὐτῷ τούτῳ σοφώτερος εἶναι, ὅτι ἃ μὴ οἶδα οὐδὲ οἴομαι εἰδέναι → I seem, then, in just this little thing to be wiser than this man at any rate, that what I do not know I do not think I know either

Plato, Apology 21d

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Russian (Dvoretsky)

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