"not to know of what things one should demand demonstration, and of what one should not, argues want of education."

ἔστι γὰρ ἀπαιδευσία τὸ μὴ γιγνώσκειν τίνων δεῖ ζητεῖν ἀπόδειξιν καὶ τίνων οὐ δεῖ·

     Aristotle, Metaphysics IV.4 (1006a), trans. W. D. Ross.