This book focuses on the relationship between the process of production of commodities and the process of social reproduction of the labouring population, and seeks to restore that problematic relationship to the central place it had in the analysis of Smith, Ricardo, and Marx. The argument is directly opposed to that of the wages-fund theorists, who rejected the classical view of labour as a very special type of commodity whose price was determined exogenously by material, historical and institutional factors. By substituting a strict supply-and-demand mechanism they and their followers effectively removed the whole question of social reproduction from economic theory. This rendered marginal or analytically invisible certain fundamental aspects of the system. In this investigation the author draws on the history of economic thought, social history, and applied economics, using the surplus definition of profit. The resulting perspective, centred on the relation between production and social reproduction, opens new directions for economic analysis.