Excerpt from Essays on the Sociology of KnowledgeWhen Karl Mannheim died early in 1947 in his fifty-third year, he left a number of unpublished manuscripts in varying stages of completion. At the invitation of Dr. Julia Mannheim, the authors widow and life-long collaborator, I assisted in setting up an editorial team selected from Mannheim's friends and former students, for the purpose of making at least part of that material available for publication. Furthermore, we felt that Mannheim's German writings had retained their full significance and ought to be reproduced in a form accessible to the English-speaking public. In all those decisions we were guided by the conviction that not only do the ideas laid down in these writings form an essential key to the full understanding of Mannheim's work, but they contain a most important and topical contribution to social theory as well as an impetus for social action.The present volume is the sequel to Freedom, Power, and Democratic Planning, which was published in 1950. It contains six essays which Mannheim wrote and published in German scientific magazines between 1923 and 1929: elaborations of one dominant theme, the Sociology of Knowledge, which at the same time represents one of Mannheim's main contributions to sociological theory. During the fifteen years since Mannheim's Ideology and Utopia was first published in this country, the Sociology of Knowledge has moved into the centre of discussion among sociologists and philosophers. The ideas laid down in this new volume should greatly help in clarifying the important issues.The task of translating and editing the German text was performed by Dr. Paul Kecskemeti, Research Associate of the Rand Corporation, Santa Monica, California. He has also contributed an introduction on the history of the problem, and on the treatment it received at successive stages of Mannheim's work.