Natural resources, thermodynamics and economic theory of production: a historical and methodological perspective.

Summary This thesis examines the methodological issues raised by the inclusion of the physical dimension of the economic process in economic theory. To this end, it focuses on the thermodynamic conception of the economy, developed in particular by Nicholas Georgescu-Roegen and Robert Ayres. More precisely, this thesis studies the way in which the thermodynamic conception of the economy is embodied in two formal representations of production, the neo-thermodynamic theory and the flow-fund theory, and how these approaches confront the neoclassical theory of resources. In order to understand the methodological issues associated with these various theories, the thesis focuses on issues related to modeling and interdisciplinarity. It shows that neoclassical resource theory and neo-thermodynamic theory share a common conception of modeling, which is reflected in the use of aggregate production functions. However, this representation of production proves inadequate to account for the physical dimension of production, both conceptually and empirically. On the contrary, the flow-fund theory constitutes a radical methodological break with the aggregate production function. It is better able to grasp the physical dimension of production from a conceptual point of view, but suffers from a lack of application. Overall, the thesis shows that methodological issues related to modeling should receive more attention when it comes to accounting for the physical dimension of the economic process.