Truth and Premiss Adequacy

It is a commonplace that to appraise an argument, or the inference it invites, 1 we must determine the adequacy of the premisses on which the argument or inference depends. Among informal logicians there is a growing consensus that, in the context of appraisal, truth does not suffice as a criterion of premiss adequacy (for example, Govier 1987, Feldman 1994). In that consensus, even if a premiss is true, it does not provide a good reason for accepting a conclusion unless it – the premiss is reasonable to accept. Using the term ̳acceptable‘ normatively, and supposing that a premiss is acceptable if and only if it is reasonable to accept it, this amounts to the view that acceptability is a necessary condition of premiss adequacy.