The disciplinary influence of physics, biology, and chemistry on economic modelling: Overview and implications for understanding agricultural change

Economic research on structural change in agriculture has repeatedly induced controversies about basic theoretical concepts, such as rational behaviour and equilibrium, and their analytical and political implications. To contribute to the epistemological dimension of this debate, the article gives an overview of three paradigms to economic modelling whose proponents have been inspired by physics, biology, and chemistry. The key concepts of general equilibrium theory, evolutionary economics and the “social chemistry” of Jon Elster are presented and compared. While all keep the idea that intentional individual action can explain aggregate outcomes that are nevertheless unintended, they differ in assumptions concerning preferences and the characteristics of coordination mechanisms. There is no consensus on what counts as a good scientific explanation. Similarly, views differ to what extent a spontaneous order in the economy has desirable properties. The emerging theoretical heterogeneity, I conclude, provides new opportunities for understanding agrarian change in contemporary society, of which a few are outlined.