Truthmakers and Predication

To what extent do true predications correspond to truthmakers in virtue of which those predications are true? One sort of predicate which is often thought to not be susceptible to an ontological treatment is a predicate for instantiation, or some corresponding predication (trope-similarity or set-membership, for example). This paper discusses this question, and argues that an "ontological" approach is possible here too: where this ontological approach goes beyond merely finding a truthmaker for claims about instantiation. Along the way a version of the problem of the regress of instantiation is posed and solved. A theory of truthmakers has often gone hand-in-hand with a theory of facts, or states of affairs. In one direction, this seems understandable: if, for whatever reason, one thinks that there are facts in the world, and especially if they are abundant, so that whenever a proposition "p" is true, there exists a fact that p (and if no "false facts" or other such things exist), then facts make for tempting truthmakers: whenever a proposition is true, then necessarily there is something which makes that proposition true: there is a fact that p. Truthmaker theorists would typically like something stronger: they would like the necessity connecting the existence of truthmakers and the truth of the corresponding proposition to be de re rather than de dicto: not just that necessarily, when p is true there is a fact that p, but also that for any fact that p, necessarily when it exists p is true. (This would not be the case, were facts to have their truth-making features contingently, as in Parsons 1999). One dream is to have a theory in which truth supervenes on being, in the sense that there can be no difference in what propositions are true without a difference in what exists (the converse would also presumably hold, but this is uncontroversial, or should be). In this sort of theory, the facts, or states of affairs, can be identified with truthmakers. I will leave to others for now the task of explaining why we might want a world of states of affairs (a world of facts, and therefore things). But it is tempting for a few reasons: it copes well with our pre-theoretical habit of employing quite general linguistic procedures to use expressions apparently referring to states of affairs in subject positions in sentences and employing quantification over them; it provides a smooth theory of events—if we are going to have a thing every time there is a change, then why not when things stay the same? (Shouldn't we think that persistence and stability are events, albeit boring ones?) and it provides for causal relata which are much easier to systematically fit into a theory of causation (see Menzies 1989). Finally, there is the push to truth-makers, or facts, from a correspondence theory of truth—where true claims correspond to pieces of the world. If the world must have different pieces in order for different claims to be true, then facts seem to be an appropriate sort of building block to think of the world as being made of. With facts in place, all sorts of claims can have ontological underpinnings all sorts of claims can have facts as their truthmakers. The truth of "The electron is spin up.", for example, is not merely underpinned by the electron (the existence of which is presumably a necessary condition for the truth of the statement): it is also underpinned by the fact that the electron is spin up. This fact is something in the world, and in an obvious respect the assertion of the existence of this fact amounts to much the same as the assertion that the electron is spin up, given a background theory of facts. (I have deliberately picked a very simple example: if there are complex, non-fundamental facts of the sort we believe in—e.g. that a given chair is wooden—this fact will itself be constituted from more simple facts). Note, however, that we need not say that the claims "the electron is spin up" and "the fact that the electron is spin up obtains (or exists)" literally mean the same thing, when the latter claim is intended literally as the assertion of the existence of a fact of a certain sort. I take a fact's obtaining and a fact existing to amount to the same thing. This is not a universal usage: there are those who take talk of the existence of facts to be a category error, and those who think that all possible facts exist, but only the privileged actual few obtain (see e.g. Plantinga 1974). My usage of “fact” here is also at variance with those who use “fact” to refer to true propositions. Of course there will be those who will want to claim the two sentences mean the same thing. But there are all sorts of reasons someone may deny that “the electron is spin up” and “the fact that the electron is spin up obtains” mean the same thing. A nominalist, for instance, may accept the former and reject the latter: presumably they will thus want to distinguish the meanings of the two. Or one might think that the reference of the noun phrases of the two sentences are different: the former may express a fact, while the latter explicitly refers to it, for example. Or one might think it a matter of synthetic metaphysical discovery (albeit perhaps one implicit to some degree in our pre-theoretic metaphysics) that the former is true just in case the latter is: in which case one will not 2