Abstract

Laws of nature have two characteristic features. They are general, in that they apply across all situations of a given kind – although they are typically restricted to particular domains. They are also modal, in that they apply across possible situations as well as actual situations. This simple account captures the core features of laws and their differences across distinct fields, and it helps to explain why laws are less prominent in some fields than in others. The most fundamental laws of physics are a special case, in that they are maximally general: they apply to all possible situations whatsoever. This provides a principled basis for a reductionist – or, to use a softer term, physicalist – view of nature. Any plausible reductionism, however, still recognizes a rich world of explanations beyond physics. In domains such as biology where laws retain important explanatory power, as well as in more anarchic domains such as history, physics is not and can never tell the whole story – and physics itself is part of the explanation for why that is so.