Raymond Aron is an exceptional figure among twentieth-century sociological and political thinkers. The book focuses on the sociological work of this author of the century, who analyzed his age both in its grand-scale political and socio-economic traits and in the complex social ramifications of its day-to-day life. Aron experts from a total of seven countries examine his sociology in detail starting with his epistemological studies on the limits of objective knowledge in history and the social sciences in which he moves away from Durkheim's approach and instead adopts Max Weber's sociology of understanding. His comparative sociology of industrial society in its market economy and planned economy variants, its social stratification, the structure of the ruling elites and the pluralistic and one-party political regimes are presented, as is Aron's analysis of the dialectic of modern society between the idea of equality and the authority structures in the state and the economic process. This is accompanied by Aron's lifelong criticism of those intellectuals who hope that a messianic ideology will abolish all social contradictions.