Within the depth-psychology corpus, pessimism is far from a single, stable attitude; it constitutes a contested philosophical inheritance that each major tradition must position itself against or appropriate. The dominant axis of tension runs between Schopenhauer’s metaphysical pessimism — the judgment that the world as it is ought not to be, grounded in the tyranny of the will-to-live — and Nietzsche’s radical counter-move, which distinguishes a ‘pessimism of weakness’ (decadent, life-denying, Schopenhauerian) from a ‘pessimism of strength’ (Dionysian, vitality-affirming, tragic). This Nietzschean reversal saturates the corpus: Dionysian pessimism becomes not a negation of life but its fullest affirmation through suffering. A secondary line runs through Gnostic and Jungian thought, where ‘cosmic pessimism’ — the recognition of the soul’s fallen existential condition — is held in deliberate tension with eschatological hope, such that the pessimistic diagnosis of the present is instrumentalized toward redemption rather than despair. William James maps yet another register, treating philosophies of despair (Stoic, Epicurean, and the broader ‘sick soul’) as developmental stages in the psyche’s confrontation with mortality, demanding religious or transnatural resolution. Neumann links deflationary pessimism to the shadow side of consciousness. Across these voices, pessimism functions less as a conclusion than as a diagnostic moment — a necessary passage, potentially generative, always requiring a response.