"Pierre Ansart's book, commissioned by Georges Balandier for a series that included Henri Lefebvre's Sociology of Marx, is a clear and authoritative guide to its subject by one of the most important commentators on Proudhon. It is excellent news that the book is to be made available in English, and that a book by Pierre Ansart has finally been translated. Anyone wanting to learn about Proudhon but perhaps daunted by the sheer bulk of Iain McKay's wonderful Property is Theft! Proudhon anthology now has a book to read in advance that will light their way to engaging with Proudhon." –Dr. Michael Tyldesley, Emeritus Honorary Fellow, Department of History, Politics, and Philosophy, Manchester Metropolitan University