Cournot's trade theory and its neoclassical appropriation: Lessons to be learnt about the use and abuse of models

This paper seeks to rehabilitate the trade theory of Augustin Cournot. In contrast to the widespread awareness among neoclassical economists of Cournot's contribution to microeconomics, there is general ignorance of his trade theory, which an earlier generation of neoclassical theorists attributed to its erroneous conclusions. I dispute this view and attempt to show the internal consistency of Cournot's trade analysis. While the assumptions underpinning his trade theory could be considered extreme, they need to be understood in the light of his methodological commitments, which included a rejection of utility in the theory of wealth, and a dismissal of Say's law regarding general employment. Furthermore, I argue that the assumptions underpinning neoclassical trade theory are no less extreme, even as their theoretical conclusions are (similarly) logically consistent. All of this serves to highlight the insufficiency of theoretical rigour in establishing the relevance of a theory; the importance of history of thought in reminding us that more than one theoretical perspective exists; and, of course, the indispensability of empirical engagement in trying to arbitrate between contrasting theoretical positions.