All that I know is nothing - I'm not even sure of that.

There is a stupid humility that is quite common and when a person is afflicted with it, he is once and for all disqualified for being a disciple of knowledge.

The only good is knowledge and the only evil is ignorance.

Nothing is so well learned as that which is discovered.

There is no learning without remembering.

To know, is to know that you know nothing. That is the meaning of true knowledge.