The usage of 'collective' concepts such as Society, State, Church and Class is essential to both the social sciences and to everyday discourse. But what in reality corresponds to such concepts? Proponents of methodological individualism argue that it is individual human action, with its unintentional and unpredictable consequences, which shapes any collective concept. Individualism in Modern Thought is a comprehensive survey of methodological individualism in social, political and economic thought from the Enlightenment to the 20th Century. Exploring the works of such figures as de Mandeville, Smith, Marx, Spencer, Durkheim, Simmel, Weber, Hayek, Popper and Parsons, this study underlines the contrasts between methodological collectivism and methodological individualism. The detailed analysis offered here also reveals the theoretical presuppositions behind the collectivist and individualist traditions and the practical consequences of their applications. Infantino concludes in favour of individualism. This work touches upon issues in social and political theory, intellectual history, political philosophy, political economy and sociological theory. The relationship between the individual and the constitution of society is of key interest to Infantino, who draws upon the ideas of Hayek to develop his own unique approach to the issues examined.