Abstract
Franz Brentano is known today primarily for his contributions to theoretical philosophy, especially the philosophy of mind. But much of his thinking was devoted to moral philosophy, and The Origin of Our Knowledge of Right and Wrong is his most important text in this area. In what follows, I (1) describe the main tenets of Brentano’s moral philosophy, (2) explain its historical and intellectual significance, and (3) offer a guide to the text, including the innovations in the present edition.