Friedrich Koppen, a German philosopher, born in Lubeck, April 21, 1775, died in Er-langen, Sept. 5, 1858. He studied theology in Jena, but he attended also the lectures of Rein-hold and Fichte, and after spending a year in Gottingen he published his first work, Abhand-lung uber Offenbarung, in Bezug auf Kant'sche und Fichte'sche Philosophie (Lubeck, 1797), which passed through several editions. Next appeared his polemical disquisition on Spelling's philosophical system, entitled Schelling's Lehre, oder das Ganze der Philosophie des abso-luten Nichts (Hamburg, 1803). He adopted in general the opinions of Jacobi, and his subsequent works, Darstellung des Wesens der Philosophie (1810), Philosophie des Christenthums (1813 - '15), Politik nach Platonischen Grund-sdtzen (1818), and Rechtslehre nach Platonischen Grundsatzen (1819), attempt to demonstrate the compatibility of critical philosophy and Christianity, basing faith and morality on personal consciousness. He preached in Bremen from 1804 to 1807, and was afterward professor in the university of Landshut until its dissolution in 1826, when he accepted a chair in Erlangen. In 1840 he published anonymously a Philosophie der Philosophie.