 Questions about the rationality (or reasonableness or justifiedness) and import of epistemic self-doubt can be developed as questions about whether and how to respect evidence about one’s evidence. Higher-order evidence is evidence about what evidence one possesses or what conclusions one’s evidence supports (see entry on  evidence).  This issue about the upshot of higher-order evidence does not in the first instance depend on whether we take such evidence as necessary for justification of first-order beliefs. The question is how our beliefs should relate to our beliefs about our beliefs when we do happen to have evidence about our evidence, as we often do (Feldman 2005; Christensen 2010a; Kelly 2005, 2010).