On the Genealogy of Morality, or On the Genealogy of Morals , subtitled "A Polemic", is a book by German philosopher Friedrich Nietzsche, composed and first published in 1887 with the intention of expanding and following through on certain new doctrines sketched out in his previous book Beyond Good and Evil. The most straightforward of Nietzsche's books and the least aphoristic in form and style, it is considered by some Nietzsche scholars to be a work of sustained brilliance and power, and Nietzsche's masterpiece.