"One is not born a genius, one becomes one."

"The world is not a collection of things, but a collection of relationships."

"I am incapable of conceiving infinity, and yet I do not accept finity. I want this adventure that is the context of my life to go on without end."

"In the face of an obstacle which is impossible to overcome, stubbornness is stupid."

"To be free is not to have the power to do anything you like; it is to be able to surpass the given toward an open future."