Doubtful Assertion.—The present subjunctive with μή may express a doubtful assertion, with μὴ οὐ a doubtful negation. The idea of apprehension or anxiety (real or assumed) is due to the situation. A touch of irony often marks this use, which is chiefly Platonic. With μή (of what may be true): μὴ ἀγροικότερον ᾖ τὸ ἀληθὲς εἰπεῖν
ἀλλὰ μὴ οὐχ οὕτως ἔχῃ
μὴ οὐκ ᾖ διδακτὸν ἀρετή
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].