Now published in English, this work takes a structuralist approach to the relation between Nietzsche's thought and his life. The author emphasizes the centrality of the notion of eternal return for understanding Nietzsche's propensities for self-denial, self-reputation and self-consumption. Nietzsche's ideas did not stem from personal pathology, according to Klossowski. Rather, he made a pathological use of his best ideas, anchoring them in his own fluctuating bodily and mental conditions. Thus Nietzsche's belief that questions of truth and morality are basically questions of power and fitness, resonates dynamically and intellectually with his alternating lucidity and delirium.