It seems rather obvious that the world could have been different. Whilst contingentists maintain that there might have been things which might not have existed, necessitists maintain that necessarily everything necessarily exists. Some contingentists also maintain that various abstract objects like properties, propositions and relations only contingently exist. For instance, many philosophers think that, had Christopher never existed, there would be no such thing as the property of being Christopher, the relation of being 10 feet away from Christopher, or the proposition that Christopher is cool.
In this thesis, Christopher James Masterman draws out the consequences of being a contingentist about abstract objects like propositions for how we should understand talk of possible worlds, or ways the world could have been. A central concern of the thesis is how useful a commonly drawn distinction between truth in a possible and truth at a possible world is for the contingentist. According to this distinction, we should not just consider which propositions would be true, were such-and-such a possible world actual. Instead, we should also consider which propositions are true at a possible world, considering things from the ‘perspective’ of the actual world.
Masterman argues that, contrary to its critics, this distinction is intelligible and can help clarify some issues for the contingentist. However, Masterman also argues that there are deep problems in formulating adequate and systematic contingentist theories of modality in terms of possible worlds. The thesis is made up of several self-standing papers that collectively contribute to one overarching argument that such a distinction is intelligible and helpful to the contingentist; but only when applied in a careful, and piecemeal manner.
Christopher James Masterman successfully defended his dissertation on 17 February 2023.
Trial lecture
Designated topic: "Present and critically evaluate Williamson's arguments for necessitism"
Evaluation committee
Professor Christopher Menzel, Texas A&M University (first opponent)
Assistant Professor Nathan Wildman, Tilburg University (second opponent)
Professor Greg Restall, University of St. Andrews (third opponent)
Associate Professor Karen Crowther, University of Oslo (committee administrator)
Chair of the defence
Professor Bjørn Torgrim Ramberg
Supervisors
Professor Peter Fritz, University of Oslo
Professor Franz Berto, University of St Andrews