The neurologist Sigmund Freud suspected the mania of syphilis could have benefited Nietzsche’s work. Freud remarked: “It is the loosening process resulting from the paresis [syphilis-induced inflammation of the brain] that gave him the capacity for the quite extraordinary achievement of seeing through all layers and recognizing the instincts at the very base. In that way, he placed his paretic disposition at the service of science.”7
