"To know what you know and what you do not know, that is true knowledge."

"Patience is the companion of wisdom."

"The only thing we have to fear is fear itself."

"We don't see things as they are, we see them as we are."

"He who has a why to live can bear almost any how."

"It is not that I'm so smart. But I stay with the questions much longer."

"The only thing I know is that I know nothing."

"Silence is a source of great strength."