Which Universals are Natural Laws?

Abstract

In What is a Law of Nature? (1983), David Armstrong defends the view that laws of nature are relations between universals and also, thereby, universals themselves. (Tooley and Swoyer hold similar views, though Tooley says that what makes nomological statements of laws true are contingent relations among universals whereas Swoyer holds that the required relations hold by metaphysical necessity.) But Armstrong doesn’t simply hold that laws are some relationships or other between universals. For he claims that they are first-order universals (pp. 89–90). Each ordinary law—for example, some causal law—is numerically identical to some first-order universal. This is a striking, seemingly incredible hypothesis. What is Armstrong thinking of when he says (1983, p. 90):

I propose that the state of affairs, the law, N(F,G), is a dyadic universal, that is, a relation, holding between states of affairs. Suppose that a particular object, a, is F, and so, because of the law N(F,G), it, a, is also G. This state of affairs, an instantiation of the law, has the form Rab, where R = N(F,G), a = a’s being F, and b, = b’s being G: (N(F,G))(a’s being F, b’s being G).

This chapter appeared in an abbreviated form in the Australasian Journal of Philosophy, 1994, 72, 492–496 and is a revised version of “Which Universal?”—which was read to the Philosophy of Science Association, Evanston, Illinois, October 30, 1988.