The most influential German philosopher of the early and mid-eighteenth century was born at Breslau. He studied mathematics at the University of Jena and, after a period at Leipzig, was appointed professor of mathematics at the University of Halle. On the recommendation of Leibniz, he was elected to the Berlin Academy in 1711. Wolff's rationalist views in theology and his defense of causal determinism (albeit a version that was supposed to be compatible with freedom of the will) made him enemies among pietists in both the university and the Prussian court. In 1723 they prevailed upon the brutal, ignorant militarist King Frederick William I to deprive Wolff of his professorship and put a… price on his head, giving him only 48 hours to leave Prussian domains under penalty of death. He was welcomed at the Calvinist university of Marburg, where he remained until 1740. Upon Frederick William's death, he was recalled in triumph by the new Prussian king, Frederick the Great. Wolff was made not only professor of law at Halle but also chancellor of the university, a privy counselor to the crown, and a baron of the Holy Roman Empire. Wolff's early works at Halle were written in German, but he produced most of his writings at Marburg, where it was more suitable that they be in Latin. He was an extremely prolific writer of encyclopedic scope, combining Leibnizian metaphysics and physics with Scholastic Aristotelianism, and creating a vast philosophical system that encompassed theories of metaphysics (or ontology), psychology, cosmology, theology, ethics, and natural right. In the first half of the eighteenth century, Wolff's system was dominant throughout the German universities, and his influence was perpetuated through the work of his many students and followers, including A. G. Baumgarten, H. F. Meier, and Martin Knutzen, Kant's teacher. Soon after Wolff's death his views were challenged by C. A. Crusius and criticized by the popular Enlightenment philosophers centered in Berlin, though some of them (including the leading philosopher among them, Moses Mendelssohn) always remained in substantial agreement with Wolffian doctrine. Wolff's influence finally ended in the last years of the eighteenth century, when German philosophy was swept up in the revolution made possible by Kant.