A Revisionary Account of Actualism and Possibilism

Possibilism is the position that it is possible to make a veridical statement about something, which doesn’t exist. Based on this observation, actualism and possibilism can be defined in first-order predicate logic by means of one or more existence predicates. It is argued that an analogous distinction can be made in the realm of first-order modal logic, and that this distinction ought to be accepted in the modal case, if it is accepted in the non-modal case. Given this trivializing perspective on possibilism versus actualism, other notions of actualism and possibilism based on the validity of the Barcan Formula and its converse have to be rejected. By taking a look at examples of different sorts of possibilia, it is made plausible that possibilism is indispensable in order to deal with fictional entities and doxastic objects. The purpose of this article is to advocate one of the simplest possible distinctions between actualism and possibilism. According to this approach, the possibilist asserts that there are multiple notions of existence and objects can exist in various ways, whereas the actualist asserts that there is only one kind of existence. While this position is certainly not new, it has rarely been made explicit, perhaps because its formulation is rather trivial in first-order predicate logic. But when transferred to first-order modal logic, this view is much less