JACOBI, FRIEDRICH HEINRICH Ger man philosopher, was born at Dusseldorf on Jan. 25, 1743. He was educated at Geneva for a commercial career, but in 1770 gave up the management of his father's business, and became a member of the council for the duchies of JUlich and Berg, where he distinguished himself by his ability in financial affairs, and his zeal in social reform. Jacobi's interest in literary and philosophic matters led him to found with C. M. Wieland a new literary jour nal, Der Teutsche Mercur, in which some of his early economic essays were published. Here too appeared in part his Edward Allwills Briefsammlung (1776), a combination of romance and speculation. This was followed in 1779 by Woldemar, a phil osophic novel. A conversation with Lessing in 1780, in which Lessing avowed that he knew no philosophy, save Spinozism, led him to study Spinoza's works. This resulted in his Briefe fiber die Lehre Spinozas (5785; 2nd ed., 1789) in which he strenuously objected to Spinoza's method of demonstration in Philosophy, and drew upon himself the enmity of the Berlin clique, led by Moses Mendelssohn. In his work, David Hume fiber den Glauben, oder Idealismus and Realismus (1787), Jacobi identified faith or belief with the immediacy of experience, and critically examined the subjective idealism of Kant.
On the outbreak of the war with France he moved to Holstein, and in 1801 published his important Uber das Unternehmen des Kriticismus, die V ernunft zu V erstande zu bringen. During the same period the accusation of atheism brought against Fichte at Jena led to the publication of Jacobi's Letter to Fichte in which he made more precise the relation of his own philosophic principles to theology, and set forth his efforts to establish theism. Jacobi received a call to Munich in connection with
the new academy of sciences in 1804, and from 1807 to 1812 was president of the academy. In 181i appeared his last phil osophic work, Von den gottlichen Dingen, directed against Schelling. Jacobi died on March io, 1819.
The philosophy of Jacobi is an attempt to define the spheres of reason and of faith. For him, reason is purely elaborative, its results never transcending the material supplied to it by the senses. But besides the things of the senses spiritual things are involved in our experience, and to these the exact method of scientific understanding cannot be applied without ending, as Spinoza does, in atheism and fatalism. Spiritual things are known only in an immediacy of experience ; even God is found by finding ourselves in Him, and certainly, freedom as self-activity can be apprehended only by intuition. This appreciation of the richness of experience made Jacobi, one of the chief champions of the Geffihlsphilosophie movement.
The best introduction to Jacobi's philosophy is the preface to vol. 2 of the Works, 6 vols. Leipzig (1812-20), and Appendix 7 to the Let ters on Spinoza's Theory. Jacobi's Auserlesener Briefwechsel has been edited by F. Roth in 2 VO1S. (1825-27). See also J. Kuhn, Jacobi and die Philosophie seiner Zeit (1834) ; F. Deycks, F. H. Jacobi im Ver hdltnis zu seinen Zeitgenossen (1848) ; H. Mintzer, Freundesbilder aus Goethes Leben (1853) ; E. Zirngiebl, F. H. Jacobis Leben, Dichten, and Denken (1867) ; F. Harms, Uber die Lehre von F. H. Jacobi (1876) ; L. Levy-Bruhl, La Philosophic de Jacobi (1894), and H. W. Crawford, The Philosophy of Jacobi (New York, igo5).