Scientific Realism Under Fire

Michele Pizzochero (University of Bath & Harvard University)

13 December 2024, 16:00 (Lisbon Time – WET)

Faculdade de Letras de Lisboa

Sala Mattos Romão [C201.J] (Departamento de Filosofia)

Abstract: Structural realism and entity realism are two widely discussed forms of scientific realism that seek to identify those claims within scientific theories that warrant ontological commitment. Broadly, structural realism holds that belief should be accorded to relations, while entity realism (especially in the version articulated by Ian Hacking) endorses belief in the entities susceptible to manipulation. Both views assert that these claims—relations or entities—underlie the empirical success of science and persist amidst theory change. In this talk, I will challenge both structural and entity realism using the historical case of phlogiston, a fire-like element posited by eighteenth-century chemists that was ultimately deemed non-existent. Despite its referential failure, the phlogiston theory was empirically successful, generating genuine predictions and unifying diverse phenomena. Drawing from this episode, I will develop a twofold argument. First, against structural realism, I will argue that the set of empirically successful relations identified within phlogiston theory was not retained in subsequent scientific theories. Second, against entity realism, I will argue that phlogiston, despite its non-existence, enjoyed manipulative success. Overall, these arguments cast doubt on the general applicability of structural and entity realism as reliable guides to track reality in the face of theory change.