The discipline of suffering, of great suffering - do you not know that it is this discipline alone that has produced all the elevations of humanity so far?

If we train our conscience, it kisses us while it hurts

Every attainment, every step forward in knowledge, follows from courage, from hardness against oneself, from cleanliness in relation to oneself.

No one can draw more out of things, books included, than he already knows. A man has no ears for that to which experience has given him no access.

The happiness of man is: I will. The happiness of woman is: he wills.

In heaven, all the interesting people are missing.

Asceticism is the right way of thinking for those who have to extirpate their sensual drives because they are ravening beasts of prey. But only for those!