 Some philosophers have also argued that certainty is the norm of practical reasoning: one can rely on p in relevant practical reasoning just in case one is certain that p (Beddor 2020a). The argument for the certainty norm depends on two premises. First, if one is genuinely relying on the premise that p, one is psychologically certain that p. If one has a lower credence with respect to whether p, one is not in fact relying on p but instead on the proposition that it is likely that p. Second, the epistemic norm for psychological certainty is epistemic certainty. To be psychologically certain with respect to a proposition for which one does not have epistemic certainty is to violate Hume’s dictum that “A wise man...proportions his belief to the evidence” (Hume 1748 [2007]).