The German historian and philosopher Wilhelm Christian Ludwig Dilthey (1833-1911) held that psychological principles should form the basis of historical and sociological research.

Wilhelm Dilthey was born in Biebrich, a village in the Rhineland, on Nov. 19, 1833. His family was intimately connected with the dukes of Nassau, serving for generations as chaplains and councilors. His early education was at a local gymnasium, from which he graduated in 1852. Following family tradition, Dilthey entered the University of Heidelberg to study theology. After three semesters he moved to Berlin for historical studies under Friedrich Trendelenburg. To please his father, he took the examination in theology and preached his first sermon in 1856. His preferred occupation was secondary teaching, but after 2 happy years he was forced to give this up as a result of persistent ill health. The next half-dozen years were spent in historical research and philosophical study at Berlin.

In 1864, with an essay on the ethics of Friedrich Schleiermacher, Dilthey entered university teaching. In 1866 he was called to Basel; in 1882, after brief tours in Kiel and Breslau, he returned to Berlin as professor of theology, a post he held until 1905. In 1874 Dilthey married Katherine Puttmann, and the couple had one son and two daughters. He died on Oct. 3, 1911, in Seis.

Dilthey published little during his lifetime, but since his death 14 volumes of collected writings have appeared. These include profound essays in intellectual history and original work on the philosophy of the mind. He made repeated efforts to arrive at general categories for interpreting comparative Weltanschauungen (philosophies of life). In imitation of Immanuel Kant's opus, Dilthey aspired to write a "Critique of Historical Reason," tracing the emergence and evolution of the great systems of thought. Dilthey concluded that no overall synthesis of these varying outlooks was possible but that an awareness of a certain historical relativity was the condition for intellectual liberation and creative work.

Dilthey argued convincingly for historical interpretation in all inquiries into man and his culture. Human life and creativity cannot be understood abstractly but only as part of a historical process. The historian must sympathetically enter into the alien cultures he seeks to understand. Much of Dilthey's work was an effort to describe the characteristic differences between this approach in historical subjects and the approach of the natural scientist toward his subject matter.