Abstract

This paper defends a Hackingian approach to the scientific realism debate by arguing against mainstream realists’ and antirealists’ common claim that no experimental arguments for the reality of posited entities can be theory-independent. Opposing this claim, I argue that some experimental arguments can warrant belief in the existence of entities without depending on the truth of the theories that posit the entities and describe their properties and the theories that explain the interactions between the entities and the experimental devices. To achieve this goal, I investigate Hacking’s case of electron spraying, the famous experiment of positioning atoms by means of a scanning tunnelling microscope, and some novel experiments that use Ashkin’s optical tweezers. By introducing the distinction between theoretical properties and ontic properties, I argue that we can build up some theory-independent criteria of reality on the basis of ontic properties. Manipulability is an ontic property and the manipulation criterion is thus a theory-independent one, which should be reexamined and used for those experimental cases along a local approach to the realism debate. Resisting the mainstream realists’ and antirealists’ objections, I contend that some experiments using optical tweezers can warrant belief in the existence of the experimented entities without depending on theories.