 Anscombe’s position on the matter is elusive, and may have to do with her normative claims about intention and belief. Is practical knowledge exempt from ordinary requirements of evidence because there is a mistake of performance, not of judgement, when its object is false? (See Anscombe 1963, pp. 4–5, 56–7; Campbell 2018a.) Would it then amount to knowledge of what is not the case? Anscombe may seem to suggest as much (Anscombe 1963, p. 82), but it is unclear whether she accepts or merely entertains this prospect.