Abstract
We argue that if there are laws of nature, then there must also be accidents. If the “laws” in a world suffice to determine the world’s entire history, then these “laws” cannot play various central roles characteristic of laws, and thus (we conclude) they are not laws at all. Many proposed accounts of lawhood (primitivist accounts, universals accounts, the Best System Account, the Package Deal Account, essentialist accounts) inappropriately permit worlds with laws but no accidents. We identify two otherwise dissimilar accounts that correctly (on our view) deem such worlds impossible; one is Humean and the other is non-Humean.