"Genealogy of Morality" or "Genealogy of Morals" was published in 1887 by the philosopher Friedrich Nietzsche. The work criticizes the prevailing morality by studying the origin of moral principles that have governed the West since Socrates. Nietzsche is against all kinds of logical and scientific reasoning applied to morality, and therefore carries out a fierce critique of speculative reason and all Western culture in all its manifestations: religion, morality, philosophy, science, and art, among others. Originally written as a "complement and clarification of Beyond Good and Evil," as stated in the introduction of the first edition, "Genealogy of Morals" became one of Nietzsche's most influential and controversial books, and Nietzsche himself is considered one of the most influential and important modern thinkers.