Humean compatibilism combines a Humean conception of laws of nature with a strong dual-ability condition for free will that requires that agents possess the ability to decide differently when they make a free decision. On the Humean view of laws of nature, laws of nature are taken to be contingent non-governing descriptions of significant regularities that obtain in the entire history of the universe. On Humean compatibilism, agents are taken to possess dual ability when making free decisions because what the (...) laws of nature will finally be is (at least partially) dependent upon how an agent decides. In this paper, I argue that the tenability of Humean compatibilism depends in part upon what theory of time is correct. More specifically, I argue that Humean compatibilism is untenable in a deterministic universe if eternalism is true. (shrink)