Awareness of ignorance is the beginning of wisdom.

If I had engaged in politics, O men of Athens, I should have perished long ago, and done no good either to you or to myself.

To know, is to know that you know nothing. That is the meaning of true knowledge. For a man who claims to have knowledge, while actually knowing nothing, is less smarter than you, who claim to know nothing.

Not by wisdom do they [poets] make what they compose, but by a gift of nature and an inspiration similar to that of the diviners and the oracles.

One ought not to return injustice, nor do evil to anybody in the world, no matter what one may have suffered from them.

Well I am certainly wiser than this man. It is only too likely that neither of us has any knowledge to boast of; but he thinks that he knows something which he does not know, whereas I am quite conscious of my ignorance. At any rate it seems that I am wiser than he is to this small extent, that I do not think that I know what I do not know.

The hardest task needs the lightest hand or else its completion will not lead to freedom but to a tyranny much worse than the one it replaces.