1 On the Boundary between Material and Formal Ontology

Two Notions of Ontology There are two main ways, philosophically, of characterizing the business of ontol-ogy, and it is good practice to try and keep them separate. On one account, made popular by Quine, ontology is concerned with the question of what there is. Since to say that there are things that are not would be self-contradictory, Quine famously pronounced that such a question can be answered in a single word—'Everything'. However, to say 'Everything' is to say nothing. It is merely to say that there is what there is, unless one goes on to specify the population of the domain over which one quantifies—and here there is plenty of room for disagreement. You may think that 'everything' covers particulars as well as universals, I may think that it only covers the former; you may think that the domain includes abstract particulars along with concrete ones, I may think that it only includes the latter; and so on. Exactly how such disagreements can be framed is itself a rather intricate question, as is the question of how one goes about figuring out one's own views on such matters. But some way or other we all have beliefs of this sort, at least as soon as we start philosophizing about the world, and to work out such beliefs is to engage in ontological inquiries. The other way of characterizing ontology stems from a different concern, and made its way into our times through Brentano and his pupils. On this second account , the task of ontology is not to specify what there is but, rather, to lay bare the formal structure of all there is, whatever it is. Regardless of whether our domain of quantification includes universals along with particulars, abstract entities along with concrete ones, and so on, it must exibit some general features and obey some general laws, and the task of ontology would be to figure out such features and laws. For instance, it would pertain to the task of ontology to assert that every entity , no matter what it is, is self-identical, or that no entity can consist of a single proper part, or that some entity can depend on another only if the latter does not depend on the former. More generally, it would pertan to the task of ontology to work out a general theory of such formal relations as identity, parthood, depend