SIGWART, CHRISTOPH WILHELM. - Philosopher, b. 27 March 1830 at Tübingen, d. there 4 August 1904. He studied philosophy, mathematics and theology at Tübingen, where his father had also taught philosophy; he later taught at the Universities of Halle and Tübingen.
S.’s principal field of study was logic and ethics, which he treated analytically, giving extensive attention to the description of thought-functions (Denkfunktionen) and to the connection and subordination of ends. Principal works: Logik (2 vols., Tübingen 1873–78; 5th ed. ed. H. Maier, ibid. 1924); Vorfragen der Ethik (Freiburg 1886; 2nd ed. Tübingen 1907); Die Impersonalien (Freiburg 1888).
BIBL.: J. Engel, S.s. Lehre V. WADSTENA. Erkennens, diss., Erlangen 1908. Further references in W. Ziegenfuss, Philosophie, Lexikon, II, Berlin 1950, pp. 535–38.