Abstract

According to a popular realist conception, the laws of nature not only describe, but indeed govern what happens in the empirical world. Thus, according to this view, laws are "modally stronger" than mere contingent, empirical regularities. At the same time, this conception has it that the laws of nature could have been other than they actually are. Thus, according to this view, laws are "modally weaker" than logical necessities. As such, this view of laws, which I call the Weak Thesis, requires that, associated with laws, is a primitive, non-logical modality, a "contingent necessity." I argue that such a primitive is mysterious and an undesirable theoretical liability that ought to be eschewed if there is an acceptable alternative theory. To this end, I argue that we ought to give up the claim that laws of nature are contingent: We should accept instead an essentialist view, which I call the Strong Thesis, according to which the laws of nature are logically necessary. On this view the things there actually are could not have been governed by laws other than the actual ones. The prima facie intuition of contingency is then explained by allowing that the laws "could have been other than they actually are" only in the sense that there might have existed other kinds of things and that those things were governed by laws other than the actual ones. The Strong Thesis has the decided advantage that it appeals only to the otherwise acceptable notions of logical necessity and contingent existence, and thereby eliminates the need for a mysterious "contingent necessity". Since it can account for the same intuitive data, the Strong Thesis, as a theory of "natural necessity," is a preferable alternative to the theory that requires us to augment our metaphysics with a mysterious, primitive modal notion