Abstract
According to a certain familiar way of dividing up the business of philosophy, ontology is concerned with the question of what entities exist (a task that is often identified with that of drafting a “complete inventory” of the universe) whereas metaphysics seeks to explain, of those entities, what they are (i.e., to specify the “ultimate nature” of the items included in the inventory). This distinction carries with it a natural thought, namely, that ontology is in some way prior to metaphysics. One must first of all figure out what things exist (or might exist); then one can attend to the further question of what they are, specify their nature, speculate on those features that make each thing the thing it is. I sympathize with that thought, but there is a major worry lurking in the background and there are several complications that emerge in the foreground. The purpose of this paper is to address such worries and complications and to come up with a plausible way of understanding the “priority thesis” that makes it both reasonable and, hopefully, useful.