Not I, but the city teaches.
A multitude of books distracts the mind.
Do it because it's in your heart. Not because you want something in return. Employ your time in improving yourself by other men's writings, so that you shall gain easily what others have labored hard for.
I only know that I know nothing
Nobody knows anything, but I, knowing nothing, am the smartest man in the world.
No one does wrong voluntarily.