Written in 1887, when Nietzsche was at the height of his powers as a philosopher and writer, On the Genealogy of Morality criticizes the idea that there is just one acceptable moral code. Nietzsche looks at the contemporary practice of morality from a historical viewpoint and adopts a naturalistic framework to understand our concepts of good and evil in the western world. He charts the origins of how we punish back to more primitive human relationships, then proposes alternative ways to shape "morality" so future human beings can flourish. Sartre's existentialism, Freud's psychoanalysis, and Foucault's postmodernism were all built on the philosophical and methodological groundwork laid by Nietzsche.