James Buchanan on the nature of choice: ontology, artifactual man and the constitutional moment in political economy

Historians of economic thought are paying greater attention to issues of social ontology (i.e. to the assumptions that economists make about the nature of social reality). We contribute to this burgeoning literature by exploring the hitherto neglected way in which James Buchanan invoked ontological considerations, concerning in particular the nature of human choice, both in criticising neoclassical economics and also in setting out his own contributions to constitutional political economy. We focus on Buchanan’s account of man as an artifactual being who has the capacity to choose the kind of person he wishes to become, in particular by selecting the kind of preferences he wishes to have and the kinds of rules under which he wishes to live. We discuss how Buchanan’s thinking on this issue was shaped by Frank Knight and G. L. S. Shackle and explain why Buchanan explicitly described his argument as ontological in nature. Finally, we contend that Buchanan’s approach would have benefited from further ontological elaboration, in two ways: first, because his arguments would have been stronger had he said more about the attributes of the human agent that help to secure their engagement in thinking creatively about themselves and the rules of society (‘the constitutional moment’), and second because his account would benefit from a deeper discussion of the interplay between human agency and social structure, especially with regard to the question of which structures might constrain or facilitate creative choices of the kind by which he set such great store.