Realism in Theory Construction

Abstract

Abstract Theoretical realism claims—against instrumentalism (Stegmüller), constructive empiricism (van Fraassen), entity realism (Hacking, Cartwright), and structural realism (Worrall)—that the theoretical terms of successful scientific theories refer to real entities in the world, even beyond the edge of direct observability, and the principles and laws in theories are true. Critical realism qualifies this view by employing the notion of truthlikeness, which in particular applies to theories containing approximations and idealizations. The notion of truthlikeness also allows a precise formulation of a charitable account of reference for theoretical terms: unlike in Fregean approaches, a theory may refer to an entity even though its description is only approximately true or truthlike. This shows that rival or successive theories may refer to the same entities in spite of the phenomenon of meaning variance or incommensurability. Illustrations of the realism debates are given in the fields of astronomy, quantum mechanics, psychology, and economics.