Karl Mannheim's work in the sociology of knowledge was con? fined to his middle period, which may be dated with some precision as the years from 1925 to 1933. His writings before 1925 deal mainly with epistemological problems and with questions about the inter? pretation of visual art. Except for some preparatory essays, it was the book Ideology and Utopia that first established Mannheim's reputation as a sociologist of knowledge. It appeared in 1929, just as the Weimar Republic had reached the high point of its intellectual productivity. Mannheim taught in Germany for only a few years. He began during the winter semester of 1926 as a lecturer in sociology in Heidelberg. I attended his inaugural lecture and decided afterwards to ask him during his office hours for permission to join his seminar. He inquired which of his writings I had already read. I was disconcerted, since I had not registered for a single course in sociology, nor had I read any of his writings. I told him that I had heard his lecture the day before and was now firmly resolved to study sociology as my main subject. Mannheim laughed. A little more than two years later, I was his first Ph.D. candidate. Soon after that, Mannheim was appointed full professor at Frank? furt, but in 1933 he became one of the first prominent academic victims of the Nazi regime. Mannheim was a Jew and his sociology was considered a destructive science. Even before Hitler assumed power, the outstanding Romanist Ernst Robert Curtius (1886-1956) had written that Mannheim's publications were an "interlacing of German Jewry with socialist or marxist or 'submarxist' teachings about society." Such vulgarities, in German academic circles no less than in popular ones, preceded the establishment of concentration camps. The German mind was endangered, wrote Curtius. This was indeed the case, and even distinguished scholars like Curtius made their contributions to it. Mannheim emigrated to London where, instead of pursuing his