The first English translation of Part 1 of the German eighteenth-century philosopher Christian Wolff's Ontology (1730). Considered one of the seminal thinkers of the German Enlightenment—a group that included Gottfried Wilhelm Leibniz, Moses Mendelssohn, Gotthold Ephraim Lessing, and Immanuel Kant—Wolff exerted his influence on the German Enlightenment through his development of a rationalist system of knowledge in which all the propositions of science are demonstrated from first principles. By grounding metaphysics in mathematics, detangling it from the Scholastics' focus on the supernatural (that which is beyond the physical), and making ontology the first philosophy—elevating it above metaphysics as a science that subsumes metaphysics (i.e., natural theology) as well as psychology and cosmology—he took the first significant steps towards a Philosophy of Enlightenment. Translated, annotated, and with an introduction by Klaus Ottmann.