is an emeritus professor from University of Paris I where he taught political sociology. He begun his research by working in this field and has been publishing several books on Tocqueville, democracy, political elites and above all, a comparative approach of the State. He then moves toward a comparative approach of contemporary jewish history by using the state as an independent variable explaining different paths of emancipation but also the birth of political antisemitism as a reaction of the presence of Jews within the strong state institutions.