I just got back from the Eidos Metaphysics conference in Geneva. It was really good fun and a great opportunity to catch up with people. One talk I went to was Robert Schwartzkopff’s, which was about the kind of metaphysical picture that is popular at Leeds. I just thought I’d write a little something about some issues that arose.

Following Kit Fine and others, we might be tempted to draw a distinction between what exists and what fundamentally exists (or really exists, or metaphysically exists, or whatever). Despite initial reticence, I’m quite attracted to this view (if you hang around in Leeds long enough, you end up being sympathetic to lots of funny views like this).

Question: what should we, qua fundamentalists, say about ontological commitment?

One view, which Ross Cameron has suggested, is that the friend of fundamentality should reject the normal Quinean criterion in favour of something else. Why? Well, I guess the idea is that the Quinean criterion will have us being ontologically committed to non-fundamental things (tables, say), because we’re committed to saying that “there are tables” expresses a truth. But fundamentalists, at least as they are often conceived, are tough desert dwellers who don’t want non-fundamental things like tables, and sums, and numbers in their ontologies. Rather, they just want the fundamental things. So, the Quinean criterion gives the wrong results and we better put something else in its place (perhaps something in terms of requirements or perhaps something in terms of truthmaking or perhaps something else). Then hopefully, we’ll be able to say that “there are tables” expresses a truth without being ontologically committed to tables and without the need to mess out with paraphrase or assertoric force or anything like that. On this view, the ontological question is “what fundamentally exists?” and the ontological project is to answer this question and not Quine’s question “what exists?”.

One thing that isn’t immediately clear, however, is that this is what the fundamentalist has to say. Here is how I tend to look at the matter at the moment. Quine asked the right question when he asked “what exists?”. And let’s spot Quine that his criterion for ontological commitment was broadly right. On this view, fundamentalists are ontologically committed both to fundamental things and to non-fundamental things. But this isn’t to say that the distinction between the fundamental and the non-fundamental doesn’t play an important role.

Suppose we have two theories, T1 and T2. T1 and T2 have exactly the same ontological commitments by Quinean standards. But T1 says that many more things are fundamental than T2 does. Both Ross and I will agree that T2 is the better theory. Ross will say that this is because T2 has less ontological commitments than T2 and that this, ceteris parabis, gives us reason to prefer T2 to T1. I can’t say that, because I’m buying the Quinean criterion, but I will say that T2 is simpler in terms of its fundamental ontology and that this, ceteris paribus, gives us reason to prefer T2 over T1. So, for both Ross and I, the distinction between the fundamental and the non-fundamental plays an important role when it comes to theory choice.

At this point, you might think that the difference between Ross’s view and mine is purely terminological. I’m identifying the ontological commitments of a theory with the entities which that theory says exists either fundamentally or derivatively. Ross is identifying the ontological commitments of a theory with the entities which that theory says exists fundamentally. But since we’re both agreeing that on the role that the distinction plays in terms of theory choice, we’re just differing over how to use the word ‘ontological commitment’.

To be honest, I wouldn’t care too much if this was the case. And I don’t think Ross would either. Now I’m going to finally get round to reading Ross’s latest paper on this topic, “Quantification, Naturalness and Ontology”, which is available from his webpage.