Nicholas Wolterstorff has claimed that David Hume hinted at a proper functionalist account that anticipates the epistemology of Alvin Plantinga. In this paper, I shall argue that we should refrain from attributing a proper functionalist epistemology to Hume. I shall first raise doubts as to how one could fit a notion of proper functioning into Hume's descriptive project. Next, I shall argue that adopting a proper functionalist epistemology would undermine some of Hume's most famous claims about causal inferences.