Department seminar: Ragnhild Jordahl, "Possible worlds, dispositions and powers"

Abstract

Modal statements, statements involving claims such as “it is possible that…” or “it is necessary that…” , are a very natural part of human language. Still these statements are problematic in the sense that there is no empirical evidence supporting a claim that something that in fact is not the case still is regarded possible, or that something that is the case is not only true here and now,  but necessary true – that reality could not have been otherwise. To make sense of these claims the term “possible world” has been widely used – and modality described in terms of possible worlds states that something is viewed as possible in the case where it is true in at least one possible world, and necessary if it is true in all of them. This worked wonders in the modal logic, but one might say that in the metaphysics of modality it has created a lot of problems. One might also ask if the possible worlds-terminology provides a satisfactory explanation of modality. This is the background for the attempt to find another way to explain modality as a fully real, fully existent feature of the world, but without resorting to possible worlds as a basic explanatory term, and the dispositional account of modality seems to provide the starting point for such an explanation. Dispositions and powers (a related but not equivalent term), and the need for a theory that is not depending on the possible worlds-terminology, will be the main topic of the talk.