Reason now gazes above the realm of the dark but warm feelings as the Alpine peaks do above the clouds. They behold the sun more clearly and distinctly, but they are cold and unfruitful.

I believe that man is in the last resort so free a being that his right to be what he believes himself to be cannot be contested.

Be attentive, feel nothing in vain, measure and compare: this is the whole law of philosophy.

One must judge men not by their opinions, but by what their opinions have made of them.

Love is blind, but marriage restores its sight.

Man is a masterpiece of creation . . .

All mathematical laws which we find in Nature are always suspect to me, in spite of their beauty. They give me no pleasure. They are merely auxiliaries. At close range it is all not true.