This is the first of Raymond Aron’s magisterial two-volume treatment of the sociological tradition – perhaps the definitive work of its kind. Aron’s study is, at its deepest level, an engagement with the question of modernity: What constitutes the essence of the new modern order that, having emerged in the eighteenth century, still forms the categories of our experience, sweeping us along toward an unknown destination? With his usual scrupulous fairness, Aron looks to the major social thinkers to discern how they answered this pressing question. Volume 1 explores three traditions: the French liberal school of political sociology, represented by Montesquieu and Tocqueville; the Comtean tradition, anticipating Durkheim in its deemphasis of the political and its elevation of social unity and consensus; and the Marxists, who posited the struggle between classes and placed their faith in historical necessity. A foreword by the eminent French philosopher Pierre Manent highlights Main Currents as a unique contribution to political philosophy as well as the history of sociological thought, while Daniel J. Mahoney and Brian C. Anderson provide an introduction situating Main Currents within the corpus of Aron’s work as a whole. This work is essential reading for philosophers, historians, sociologists, and political scientists.