Pierre and the Fundamental Assumption

Kripke's Pierre puzzle undermines some of the central epistemic intuitions that underlie traditional defences of the Fregean assumption that sentences'S believes that Fa ‘and'S believes that Fb’ can differ in truth value, even though a = b. Millian theorists have seized on this and employed the puzzle to reject the Fregean assumption itself. I argue that Millians are correct in rejecting traditional defences of the Fregean assumption, but they are wrong in rejecting the Fregean assumption itself. To this end, I offer a different argument kr the assumption, one that is not open to Kripkean/Millian objections.