Semirealism, Concrete Structures and Theory Change

Abstract

After a presentation of some relevant aspects of Chakravartty’s semirealism (A Metaphysics for scientific realism. Knowing the unobservable. Cambridge University Press, Cambridge, 2007), this paper addresses two difficulties that appear to be inherent to important components of his proposed metaphysics for scientific realism. First, if particulars and laws are concrete structures, namely actual groupings of causal properties as the semirealist contends, the relation between particulars and laws becomes also a relation between particulars with some annoying consequences. This worry—and some others—are resolved if laws are taken to be statements and particulars are construed not only as groupings of properties, but things that contain a non-conceptual ingredient which can be given in perceptual awareness. Second, on the semirealist’s view of particulars it becomes difficult to defend an epistemological version of scientific realism according to which we have good reasons to believe that the same things are referred to despite the fact that successive theories may attribute different properties to them.