Abstract

According to ontological pluralism there are several ways of being. This is so if there is an unrestricted quantifier that ranges over everything there is, and there are several semantically primitive, restricted quantifiers with possible meanings such that each restricted quantifier has a non-empty domain that is properly included in the domain of the unrestricted quantifier, the domains of the restricted quantifiers do not overlap, and the meaning of each restricted quantifier is at least as natural as the meaning of the unrestricted quantifier. My long-standing interest in the debate concerning pluralism about truth has shaped my choice of focus in this piece. According to truth pluralism there are several ways of being true. Different properties are relevant to the truth of propositions concerning different domains. The problem of mixed compounds challenges truth pluralists to provide a principled account of the truth of mixed compounds, i.e. compounds whose constituents are true in different ways. My aim here is to present and articulate a corresponding issue facing ontological pluralists: the problem of mixed beings. The problem of mixed beings challenges ontological pluralists to provide a principled account of the way in which mixed beings exist, i.e. beings whose constituents exist in different ways.