The dogmatist argues (or may argue), however, that Moore’s proof is dialectically flawed (cf. Pryor 2004). The contention is that Moore’s is unsuccessful because it is useless for the purpose to convince the idealist or the external world sceptic that there is a material world. In short, the idealist and the global sceptic don’t believe that there is a material world. Since the idealist and the sceptic don’t believe Q8, they are rationally required to distrust any perceptual evidence offered in