Abstract

Frank Hindriks has attempted to derive a variant of Timothy Williamson’s knowledge rule for assertion on the basis of a more fundamental belief expression analysis of that speech act. I show that his attempted derivation involves a crucial equivocation between two senses of ‘must,’ and therefore fails. I suggest two possible repairs; but I argue that even if they are successful, we should prefer Williamson’s fully general knowledge rule to Hindriks’s restricted moral norm.