ABSTRACT
Scientifi c realism is the ontological (or metaphysical) thesis that most of the (unobservable) entities (including objects, events, processes, properties, relations, etc.) of physical science exist mind-independently, that is, independently of our beliefs about them, our theories of them, the terms we use to refer to them, the language we use to discourse about them, our perception of them, etc. This is distinct from semantic theses often associated with scientifi c realism; these appeal to semantic items and say that most of the (physical) theories of science that we have proposed are true, or have a high degree of verisimilitude, or that many of the terms used in these theories do correctly denote. Both of these theses are distinct from a third epistemological thesis about whether or not physical theories can be items of knowledge (as distinct from mere belief), what truth-value we know the theories to have, what rational degree of belief we can have for the theories on the basis of evidence, whether or not we have made genuine discoveries of hitherto unknown entities, and the like.1 Finally, realism can be an axiological thesis about what we aim for in science, viz., truth or increasing verisimilitude, in contrast with other nonrealist aims such as empirical adequacy.
