People sometimes try to call others’ beliefs into question by pointing out the contingent causal origins of those beliefs. The significance of such ‘Etiological Challenges’ is a topic that has started attracting attention in epistemology. Current work on this topic aims to show that Etiological Challenges are, at most, only indirectly epistemically significant, insofar as they bring other generic epistemic considerations to the agent’s attention (e.g. disagreement, consistency with one’s own epistemic standards, evidence of one’s fallibility). Against this approach, we argue that Etiological Challenges are epistemically significant in a more direct and more distinctive way. An Etiological Challenge prompts the agent to assess whether her be...