mathematics
From LSJ
ἐὰν ἐκπέσῃ τὸ σιδήριον καὶ αὐτὸς πρόσωπον ἐτάραξεν καὶ δυνάμεις δυναμώσει καὶ περισσεία τοῦ ἀνδρείου σοφία (Ecclesiastes 10:10, LXX version) → If the iron axe fails, and the man has furrowed his brow, he will gather his strength, and the redoubling of his manly vigor will be the wise thing.
