I AM GREATLY indebted to Mrs. E. Llewellyn for secretarial assistance, to Donald Aldridge for designing the diagram, to Charles Taylor and Arnold Kaufman for reading the book at various stages and making valuable suggestions, and to Norman Birnbaum, Dennis Duerden and Norman Hotopf for reading parts of it and making critical or encouraging comments. The responsibility for the views expressed is of course mine only.
My philosophical debts are obvious or indicated in the text. But I should also express my thanks to the members of the Social Anthropology Department at the L.S.E., who taught me how, without prejudice to its validity, one should see a set of related ideas and practices as a system of mutually supporting, and sometimes conflicting parts, and interpret it in terms of the services it performs and the conditions it requires in the social context of which it is a part.
But my greatest individual debt, and a very considerable one indeed, is to John Hajnal, whose painstaking notes and patient discussions have helped me to be less confused than would otherwise be the case.