Madness is rare in individuals--but in groups, parties, nations, and ages it is the rule.

One will rarely err if exteme actions be ascribed to vanity, ordinary actions to habit, and mean actions to fear.
--Human, All Too Human

Man is a rope stretched between the animal and the Superman--a rope stretched over an abyss.

When Zarathustra was alone . . . he said to his heart: "Could it be possible! This old saint in the forest hath not yet heard of it, that God is dead!"
--T hus Spake Zarathustra

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.
--Ecce homo

The sick are the greatest danger for the healthy; it is not from the strongest that harm comes to the strong, but from the weakest.
--Geneology of Morals