Carl Jung contributed to psychoanalysis in an important way, but that contribution to the field is inseparable from his engagement with Nietzsche. Jung derived a wealth of insights from Nietzsche’s work, and his psychological state that deteriorated into madness. Jung’s central hypothesis is that Nietzsche was possessed by an archetype. Such archetypal inflation was the result of a deep imbalance within Nietzsche’s psyche, springing from his rejection of the spiritual.