Justification and Relative Apriority

There is obviously tension between any view which claims that the object denoted is all that names and simple referring terms contribute to propositions expressed by sentences in which they appear and the apparent a posteriority of identity statements containing different but codesignative names. Frege solved the tension by adopting a description theory of names. The direct designation theorist cannot do the same, for that would amount to abandoning the theory. Instead, she has to provide one of two solutions; (a) argue that although Hesperus is Hesperus and Hesperus is Phosphorus express the same proposition their epistemic status differs such that one's justification of the proposition expressed by the former but not the latter is a priori, or (b) argue that both Hesperus is Hesperus and Hesperus is Phosphorus express a priori truths. I will argue for a version of option (a), and that while coreferential names can be freely substituted in simple belief contexts, they cannot be freely substituted in contexts involving justification.