TRENDELENBURG, FRIEDRICH ADOLF (1802— 1872), German philosopher and philologist, was born on Nov. 3o, 1802, at Eutin, near Liibeck. He was educated at the universities of Kiel, Leipzig and Berlin. He became more and more attracted to the study of Plato and Anstotle, and his doctor's dissertation (1826) was an attempt to reach through Aristotle's criticisms a more accurate knowledge of the Platonic philosophy (Platonis de ideis et numeris doctrina ex Aristotele illustrata). He spent seven years as tutor in a private family, occupying his leisure in pre paring a critical edition of Aristotle's De anima (1833; 2nd ed. by C. Belger, 1877). In 1833 Altenstein, Prussian minister of education, appointed Trendelenburg extraordinary professor in Berlin, and four years later he was advanced to an ordinary professorship. In 1865 he engaged in an acrimonious controversy on the interpretation of Kant's doctrine of Space with Kuno Fischer, whom he attacked in Kuno Fischer und sein Kant (1869), which drew forth the reply Anti-Trendelenburg (1870). He died on Jan. 24, 1872.
Trendelenburg's Naturrecht may be taken as in a manner the completion of his system, his working out of the ideal as present in the real. The ethical end is taken to be the idea of humanity, not in the abstract as formulated by Kant, but in the context of the State and of history. Law is treated throughout as the ve hicle of ethical requirements. In Trendelenburg's treatment of
the State, as the ethical organism in which the individual (the potential man) may be said first to emerge into actuality, we may trace his nurture on the best ideas of Hellenic antiquity.
Trendelenburg was also the author of the following: Elementa logices Aristotelicae (1836; 9th ed., 1892; Eng. trans., 5881), a selection of passages from the Organon with Latin translation and notes, containing the substance of Aristotle's logical doctrine, supplemented by Erliiuterungen zu den Elementen der Aristotel ischen Logik (5842; 3rd ed. 1876); Logische Untersuchungen (1840; 3rd ed. 1870), and Die logische Frage in Hegels System, (5843), important factors in the reaction against Hegel; Histor ische Beitriige zur Philosophie (1846-67), in three volumes, the first of which contains a history of the doctrine of the Categories; Das Naturrecht auf dem Grunde der Ethik (186o) ; Liicken im Olkerrecht (187o), a treatise on the defects of international law, occasioned by the war of 1870.