NELSON, LEONHARD (1882–1927), German philosopher, a descendant of Moses Mendelssohn. Born in Berlin, he was baptized while a child. He became lecturer in philosophy in the faculty of natural sciences at Goettingen in 1909 and professor in 1919. He founded the "New Fries School," which, following J.F. Fries (1793–1873) and using psychological method, wanted to renew Kant's teaching, but on a basis entirely different from that of the Neo-Kantians. To provide a forum for this school, Nelson founded the "Discussion groups of the Fries School" (1904–08), and published many articles, the most famous of which is "Die Unmoeglichkleit der Erkenntnistheorie"; the English version of which appeared in the collection of his articles Socratic Method and Critical Philosophy (1949). His main interest was in ethics, and his own ethics are close to those of Kant but without sharing their severe pendantry. Nelson developed his ethics in Vorlesungen ueber die Grundlagen der Ethik, 3 vols. (1917–32). Volume 1 dealt with the bases of ethics, volume 2 with pedagogy, and volume 3 is devoted to the philosophy of law and politics. In politics Nelson was close to moderate Socialism, similar to that of Franz *Oppenheimer. The principles of society's existence cannot be surrendered to majority decisions, since this would abandon them to arbitrariness and chance, for one cannot be certain that the majority even knows what is best for it. His students issued some of his unpublished lectures, among them the great work Fortschritte und Rueckschritte der Philosophie; von Hume und Kant bis Hegel und Fries (1962), edited by Julius Kraft. A list of his works is to be found in L. Nelson zum Gedaechtnis (1953).
H. Falkenfeld, Kantstudien (1928), 247–55; Encyclopedia of Philosophy, 5(1967), 463–7; B. Selchow, L. Nelson, ein Bild seines Lebens (1938).
[Samuel Hugo Bergman]