Laws of Nature as Constraints

The laws of nature have come a long way since the time of Newton: quantum mechanics and relativity have given us good reasons to take seriously the possibility of laws which may be non-local, atemporal, ‘all-at-once,’ retrocausal, or in some other way not well-suited to the standard dynamical time evolution paradigm. Laws of this kind can be accommodated within a Humean approach to lawhood, but many extant non-Humean approaches face significant challenges when we try to apply them to laws outside the time evolution picture. Thus for proponents of non-Humean approaches to lawhood there is a clear need for a novel non-Humean account which is capable of accommodating these sorts of laws. In this paper we propose such an account, characterizing lawhood in terms of constraints, which are understood as a form of modal structure. We demonstrate that our proposed realist account can indeed accommodate a large variety of laws outside the time evolution paradigm, and describe some possible applications to important philosophical problems.