Is pessimism necessarily a sign of decline, decay, degeneration, weary and weak instincts? Is there a pessimism of strength? An intellectual predilection for the hard, gruesome, evil, problematic aspect of existence, prompted by well-being; by overflowing health, by the fullness of existence?
— Friedrich Nietzsche, Attempt at a Self-Criticism
(Preface to The Birth of Tragedy (1872) added in 1886, for the publication of a new edition)