ABSTRACT I hold that coreferential proper names ‘ a ’ and ‘ b ’ differ in meaning because they play different causal roles in the explanation of behaviour. I have previously rejected the Fregean view that we must believe in this difference in meaning because ‘ a = a ’ and ‘ a = b ’ differ in informativeness. Bozickovic argues that I was wrong to reject this view. I have come to agree with him, though not because I was convinced by his argument. I was wrong to think that the Fregean view rested on the ‘Cartesian’ assumption that competence with a term brings with it knowledge‐ that about meanings. The view rests rather on an assumption of knowledge‐ how . The knowledge‐how that constitutes competence with ‘ a ’ and ‘ b ’ causes ‘ a = a ’ and ‘ a = b ’ to differ in informativeness. So, there will be this difference only if ‘ a ’ and ‘ b ’ differ in meaning. These meanings, I have argued elsewhere, are causal modes of reference.
Michael Devitt (Wed,) studied this question.