“Man cannot be free if he does not know that he is subject to necessity, because his freedom is always won in his never wholly successful attempts to liberate himself from necessity. ”

“A teacher who cannot explain any abstract subject to a child does not himself thoroughly understand his subject; if he does not attempt to break down his knowledge to fit the child's mind, he does not understand teaching.”

“Man is always prey to his truths. Once he has admitted them, he cannot free himself from them.”

“man is free, in so far as he has the power of contradicting himself and his essential nature. Man is free even from his freedom; that is, he can surrender his humanity”

“I'm in prison because I'm a free man, because I found it necessary to exercise my freedom, because I accepted this necessity.”

“Without self knowledge, without understanding the working and functions of his machine, man cannot be free, he cannot govern himself and he will always remain a slave.”