It is sad not to love, but it is much sadder not to be able to love.

Science is a cemetery of dead ideas, even though life may issue from them.

Human beliefs, like all other natural growths, elude the barrier of systems.

Only he who attempts the absurd is capable of achieving the impossible.

We need God, not in order to understand the why, but in order to feel and sustain the ultimate wherefore, to give a meaning to the universe.

True science teaches, above all, to doubt and be ignorant.

Those who say they believe in God and yet neither love nor fear Him, do not in fact believe in Him but in those who have taught them that God exists. Those who believe that they believe in God, but without any passion in their heart, any anguish of mind, without uncertainty, without doubt, without an element of despair even in their consolation, believe only in the God-idea, not in God.