Debunking arguments aim at defeating the justification of a belief by revealing the belief to have a dubious genealogy. One prominent example of such a debunking argument is Richard Joyce’s evolutionary debunking explanation of morality. Joyce’s argument targets only our belief in moral facts, while our belief in prudential facts is exempt from his evolutionary critique. In this paper, I suggest that our belief in prudential facts falls victim to evolutionary debunking, too. Just as our moral sense can be explained (...) in evolutionary terms, so presumably can our tendency to judge our actions in prudential terms. And if the evolutionary explanation of our moral sense has an undermining effect, then so does the evolutionary explanation of our belief in prudential facts. This also undermines moral fictionalism, the view that we have prudential reasons to maintain moral discourse as a fiction. I consider and refute four possible objections to the suggested debunking of our belief in prudential normativity. (shrink)