One of the central debates in eighteenth-century political economy concerned the role and status of the plebeian populace. This article examines the attempts by historians to understand the nature and significance of these discussions. I argue that writers have been engaged in answering two core questions. Firstly, how did attitudes to labour develop through the course of the eighteenth century and what was the role of Adam Smith's work within this process? Secondly, what was the relationship between political economy and the socio-economic reality faced by the lower orders? In tracing the various responses to these questions, my analysis looks at both the work by historians of economics concerning the transition from mercantilism to classical political economy, and E. P. Thompson's account of the movement from ‘moral economy’ to ‘political economy’.