Heterodox economics, social ontology, and the use of mathematics

In a recent article (Lawson, 2013), Tony Lawson argues for a Veblenian interpretation of the term “neoclassical”, according to which a neoclassical economist is one whose methodology is at odds with their ontological presuppositions. This leads him to categorize many heterodox economists as neoclassical on the basis that their use of mathematical modeling is at odds with their (implicit) acceptance of an open-systems ontology. The reason is that, according to Lawson, mathematical modeling is deductivist: it presupposes that social systems are closed. The argument advanced in this paper is that this last claim is true only some of the time, and problematic only some of the time that it is true. It therefore amounts to a defense of mathematical modeling by heterodox economists that is, at the same time, sympathetic to Lawson’s claims that the social realm is structured but open and that this ontology is (implicitly) accepted by many heterodox economists.