 A different sort of question concerns how much evidence, information, or background beliefs we must set aside, and whether there are any limits on this. Intuitively, the scope of what we must set aside depends on the scope of higher-order undermining we receive, and which instances or types of reasoning are called into question. But how far can it go? What if everything is called into question? Considering this possibility leads to paradox. On the one hand, reason to universally doubt our reasoning seems to justify skepticism across the board. On the other hand, the way we would arrive at that skeptical state would be by using our reasoning… which has been, by hypothesis, called into question. Some epistemologists have suggested that since there is no stable and consistent response to such cases, we ought to conclude that universal defeat is impossible. But this response is hard to reconcile with the fact that defeat comes on a spectrum; if the extreme cases are impossible, what about the intermediate cases? (For further discussion, see Egan &amp; Elga 2005, Enoch 2010, Sliwa &amp; Horowitz 2015, Schoenfield 2015a, Christensen 2010a, 2019. See also the entry on  epistemic self-doubt  for further discussion.)