Scientific Realism Again

The present paper concerns how scientific realism is formulated and defended. It is argued that van Fraassen is fundamentally right that scientific realism requires metaphysics in general, and modality in particular. This is because of several relationships that raise problems for the ontology of scientific realism, namely those between: scientific realism and common sense realism; past and current theories; the sciences of different scales; and the ontologies of the special sciences and fundamental physics. These problems are related. It is argued that ontic structural realism, in the form of the real-patterns account of ontology, offers a unified solution to them all (or at least that it is required to do so, if it is to make good on the promise of naturalised metaphysics).