WOLFF (less correctly WOLF), CHRISTIAN German philosopher and mathematician, the son of a tanner, was born at Breslau on Jan. 24, 1679. At the University of Jena he studied first mathematics and physics, to which he soon added philosophy. In 1703 he qualified as Privatdozent in the University of Leipzig, where he lectured till 1706, when he became professor of mathematics and natural philosophy at Halle through the in fluence of Leibniz, of whose philosophy his own system is a modi fication. In Halle Wolff limited himself at first to mathematics, but presently added physics, and eventually all the main philo sophical disciplines. But the claims which Wolff advanced on be half of the philosophic reason (see RATIONALISM) appeared im pious to his theological colleagues. Halle was the headquarters of Pietism, which, after a long struggle against Lutheran dogmatism, had itself assumed the characteristics of a new orthodoxy. Wolff's professed ideal was to base theological truths on evidence of mathematical certitude, and strife with the Pietists broke out openly in 1721, when Wolff, on the occasion of laying down the office of pro-rector, delivered an oration "On the Practical Philo sophy of the Chinese" (Eng. trans. 1750), in which he instanced the moral precepts of Confucius as evidence of the power of human reason to attain by its own efforts to moral truth. For ten years Wolff was subjected to attack, until in a fit of exasperation he appealed to the court for protection. His enemies, however, told Frederick William I. that, if Wolff's determinism were recog nized, no soldier who deserted could be punished, since he would only have acted as it was predetermined that he should. Wolff was at once deprived of office and ordered to leave Prussia on pain of death. He crossed over into Saxony, where the landgrave of Hesse received him with every mark of distinction, and the cir cumstances of his expulsion drew universal attention to his teach ing at Marburg, where he was now established. Over 200 books and pamphlets appeared for or against Wolff's doctrine before 1737, not reckoning the systematic treatises of Wolff and his followers. One of the first acts of Frederick the Great was to recall Wolff (1740) to Halle. In he became chancellor of the
university, and in 1745 he received the title of Freiherr from the elector of Bavaria. But his matter was no longer fresh, he had outlived his power of attracting students, and his class-rooms re mained empty. He died on April 9, Wolff's most important works are as follows : Anfongsgriinde aller mathematischen Wissenschaften (1710; in Latin, Elementa matheseos universae, 1713-15) ; V erniinf tige Gedanken von den Kraften des menschlichen V erstandes ( I 712 ; Eng. trans. I 77o) ; Vern. Ged. von Gott, der Welt and der Seele des Menschen ( 719) ; Vern. Ged. von der Menschen Thun und Lassen ( 7 20) ; Vern. Ged. von dem gesellschaftlichen Leben der Menschen ( 721 ) ; Vern. Ged. von den Wirkungen der Natur ( 723) ; Vern. Ged. von den Absichten der natiirlichen Dinge (1724) ; Vern. Ged. von dem Gebrauche der Theile in Menschen, Tizieren und Pflanzen (1725). The last seven may be described briefly as treatises on logic, metaphysics, moral philosophy, political philosophy, theo retical physics, teleology, physiology : Philosophia rationalis, sive logica (1728) ; Philosophia prima, sive Ontologia (1 729); Cosmologia generalis (1731) ; Psychologia empirica (1732), Psy chologia rationalis (173 4 ) ; Theologia naturalis (1736-37) ; Philo sophia practica universalis (1738-39) ; Jus naturae and Jus Gen tium (1740-49); Philosophia moralis (1750-53). His Kleine philosophische Schrifteni have been collected and edited by G. F. Hagen (i736-40).