The body of enquiry known as economics grew out of the practical needs of economic life and statesmanship, and also out of philosophical speculation on the nature of man and society. Adam Smith reflects both aspects, but I would locate him predominantly in the philosophical wing. When he switched from considering the theory of moral sentiments to dealing with the causes of the wealth of nations, I don't believe that he saw himself as engaging in a fundamentally different mode of enquiry. He was, of course, concerned with practical questions--of ethical behaviour in the one case and of economic policy in the other--but discussion of both was from a broad philosophic viewpoint. Ricardo, on the other hand, seems to me to exemplify, and at a high level, someone who falls predominatly in the other wing. Although his thought was abstract, it was much more an attempt to deal pragmatically with important issues of practice than it was an attempt, in the philosophical tradition, to understand the general nature of men's interaction in society. Indeed, utilitarianism by then offered a strictly philosophic rationale for concern with practice (albeit a piggish one in some eyes) which did much to confound and confuse the dual origins of economics. Mill and Sidgwick, among others, maintained the tradition of a close connection between philosophical and economic enquiry, within the framework of a broadened utilitarianism, and the continuing affinity of the two disciplines has been exemplified more recently in the work of writers such as Rawls and Sen, not to mention the recent upsurge in discussion of economic methodology.