οὐ γάρ
From LSJ
Ἀμήχανον δὲ παντὸς ἀνδρὸς ἐκμαθεῖν ψυχήν τε καὶ φρόνημα καὶ γνώμην πρὶν ἂν ἀρχαῖς τε καὶ νόμοισιν ἐντριβὴς φανῇ → It is impossible to know the spirit, thought, and mind of any man before he be versed in sovereignty and the laws
English (LSJ)
in orat. recta, A for not, in assigning a negative reason, Il. 22.438, etc.: other Particles are sometimes put between, as οὐ μὲν γάρ 5.402; οὐ γάρ, in assent to a neg., no indeed, Pl. Tht.150a, etc. II elliptic, in interrog. replies, where yes or well must be supplied, τούτους ἀγαθοὺς ἐνόμισας;—οὐ γάρ… ; yes (or well), and aren't they? Ar. Pax970. 2 in questions, where an affirm. answer is expected, οὐ γὰρ ὁ Παφλαγὼν ἀπέκρυπτε ταύτας;did not he keep them hidden? Id.Eq.1392, cf. D.22.73, etc.