Programme
Boaz Schuman
University of Toronto
What are Modals About?
In John Buridan’s modal semantics, terms stand not only for actual objects, but for possible, non-existent ones as well. What are these non-existent possible objects, and what grounds their modal properties? In brief, their possibility and other modal properties are grounded in causality: if there exists a power to make an object, then that object is possible, whether or not it exists. Take for example a carpenter and a pile of lumber. The lumber is a possible house, because the carpenter can make it so. Such possible objects can also have necessary properties. More generally, any such object is possibly φ just in case it can be made to be not-φ without destroying it; if the alteration means destruction, then the object is necessarily φ. For example, whereas the house will remain intact if it is painted blue, it will be destroyed if it is pulverised. Thinking about modality in this way gives us a pretty broad class of possible objects and their possible and necessary properties. So many, in fact, that it’s often easier to talk about what lies beyond the boundary of the possibilia—i.e. the impossibilia. Among these impossibilia we find round squares, chimaeras—and, surprisingly, Lewisian pluralities of worlds.