This thesis concerns pluralism about truth: roughly, the theory that there is more than one way to be true. Where ‘Grass is green’ might be true in one way, ‘Eating meat is wrong’ or ‘7 > 3’ might be true in another. I am interested in showing this theory in its best light. This requires casting a critical eye over extant incarnations of pluralism, formulating new, stronger motivations in its favour, and defending it from objections.
Where most pluralists try to motivate the theory by assuming an underlying ontological diversity – in what different truthbearers are about, e.g., grass vs. wrongness vs. numbers – my arguments assume an underlying diversity, not in the world, but in our thought and talk. While ordinary discourse like ‘Grass is green’ expresses representational states (the belief that grass is green), I assume with metaethical expressivism that moral discourse like ‘Eating meat is wrong’ expresses desire-like states (e.g., disapproval of eating meat). Given this metasemantic pluralism, I provide a direct argument for thinking that truth within ordinary discourse consists in corresponding with reality, while moral truth is epistemically constrained; and I develop a novel theory of moral truth.
I go on to argue that the most prominent objections to pluralism – which concern cases where truthbearers apt for different properties are “mixed” together – in fact pose no special problems for the pluralist. I provide a pluralist-friendly metaphysics of truth for complex truthbearers that dissolves the appearance of difficulty, arguing that the truth of a complex consists in a distinct property that is grounded in the truth properties relevant for its components. And in the final chapter, I show how this independently motivated metaphysics of truth can in turn be used to dissolve the liar paradox.
