We no longer love our knowledge enough once we have passed it on.

Every philosophy is the philosophy of some stage of life.

Was aus Liebe getan wird, geschieht immer jenseits von Gut und Böse. (What is done out of love always takes place beyond good and evil.)

I call Christianity the one great curse, the one great intrinsic depravity, and the one great instinct of revenge, for which no means are venomous enough, or secret, subterranean and small enough - I call it the one immortal blemish on the human race.

I assess the power of a will by how much resistance, pain, torture it endures and knows how to turn to its advantage.

No, life has not disappointed me. On the contrary, I find it truer, more desirable and mysterious every year -- ever since the day when the great liberator came to me: the idea that life could be an experiment of the seeker for knowledge -- and not a duty, not a calamity, not trickery.

But it is the same with man as with the tree. The more he seeketh to rise into the height and light, the more vigorously do his roots struggle earthward, downward, into the dark and deep — into the evil.