A basic question in mind and metaphysics is the relation between the nature of mental content (or meaning) and the nature of the domains of entities and relations to which those contents refer or which they are about. Does an explanation of this relation require us to give meaning priority, or instead is the metaphysics of the domain always involved in explaining the content? In his new book, The Primacy of Metaphysics (Oxford University Press, 2019), Christopher Peacocke argues for the idea that the metaphysics of the domain must always be involved – that one must always draw on facts about metaphysics to explain meaning but not vice versa. Peacocke, who is Johnsonian Professor of Philosophy at Columbia University, applies his general thesis to various specific domains, such as temporal phenomena and the self, and considers how it bears on such further issues as the integration of metaphysics and epistemology and the limits of intelligibility.