This paper examines the development of Nietzsche's thought on pessimism in the light of his own reflections. Drawing on GT, the late prefaces he wrote around 1886 (GT, MA, M, FW), the fifth book of FW, and unpublished notes, it recon-structs the several meanings that Nietzsche attributes to 'pessimism.' It focuses on the complex relation between 'romantic' and 'Dionysian' pessimism. It is shown that these two forms of pessimism are rooted in Nietzsche's ambivalent metaphysical pessimism in GT, which is influenced by Schopenhauer and the tragic Greeks. This approach is distinguished from the later Nietzsche who attempts to redefine his struggle with pessimism in order to 'forget' the metaphysical background, and to understand pessimism as a symptom of historical and psychological conditions. Nietzsche consequently understands his own thought as a continuation of Schopen-hauer's critique of the Christian worldview, which leads to the problem of nihilism. Nietzsche attempts to show how it is possible to overcome romantic pessimism and European morality, if he also suffers the consequences of nihilism. In order to tackle this problem, Nietzsche formulates a dynamic of self-overcoming which needs both strength and weakness, health and sickness.
