 Friedrich Nietzsche employs a historical or “genealogical” method in On the Genealogy of Morals (1887) to critique the basic categories of Christian morality. Challenging the idea that this morality is basic to human nature, he argues that prevailing moral categories were tools intentionally wielded in a struggle for power. Ideals of humility and self-denial, for instance, were introduced by leaders of a resentful population to undermine the aristocratic values of Greco-Roman society. In Nietzsche’s account, the sources of such categories are largely cognitive and intentional, as opposed to arising from material relations, as they do in Marx’s account.