Socrates_statue_at_the_LouvreIn the best known lines from Plato’s Phaedrus:

‘But I [Socrates] have no leisure for them [other inquiries] at all.

And the reason, my friend, is this: I am not yet able, as the Delphic inscription [Gnothi Seauton] has it, to know myself; so it seems to me ridiculous, when I do not yet know that, to investigate irrelevant things.’