BRUNNER, CONSTANTIN (pen name of Leopold Wertheimer ; 1862–1937), German philosopher. He lived in Potsdam until 1933, and immigrated to Holland when the Nazis came to power. He constructed his own philosophical system. He followed Plato, and to an even greater extent, Spinoza. His major work is Die Lehre von den Geistigen und vom Volk (1908).
Central to Brunner's theory is the characterization of three different aspects of contemplation (including emotion and will): (1) Practical reason, which every human possesses and which serves one's normal needs. (2) The spiritual faculty, which rises above the relative truth residing in experience and in science, and strives toward a perception of the one eternal and absolute essence. This spiritual faculty finds expression in the artist's inspiration, in the endeavor to penetrate the mysteries of the universe as part of the pursuit of the absolute, and in philosophy as the knowledge of the eternal. Very few are endowed with this faculty. (3) "Superstition" – pseudo-contemplation, which is the mode of contemplation of most ordinary men. Unfounded belief is a distortion of the spiritual faculty. While practical reason recognizes that the "relative" is only "relative," superstition elevates what is relative to the status of the absolute. As part of his theory of society and the state, Brunner argued for total assimilation of the Jews and staunchly opposed Zionism. Among his admirers were Gustav *Landauer and Walter *Rathenau. In 1924 the Constantin Brunner Society was founded in Berlin. An International Constantin Brunner Institute exists in The Hague. Brunner's other works include Der Judenhass und die Juden (1918); Materialismus und Idealismus (1928); Von den Pflichten der Juden und von den Pflichten des Staates (1930); and Derentlarvte Mensch (1951).
Constantin Brunner Gemeinschaft, Von Constantin Brunner und seinem Werk (1927); W. Bernard, Philosophy of Spinoza and Brunner (1934); L. Bickel, Wirklichkeit und Wahrheit des Denkens (1953). add. bibliography: F. Ritter, "Constantin Brunner und seine Stellung zur Judenfrage," in: Bulletin des Leo Baeck Instituts, 51 (1975), 40–79; M. Falek, "Un philosophe méconnu – Constantin Brunner," in: Les Nouveaux Cahiers, 39 (1974–1975), 32–37; C. Brunner, Der Judenhass und die Juden (2004); J. Stenzel, Die Philosopie Constantin Brunners (2003); M. Hendirk, Constantin Brunner – Eine Einfuehrung (2000).
[Otto Immanuel Spear]