A Fregean Look at Kripke's Modal Notion of Meaning

In Naming and Necessity Kripke accuses Frege of conflating two notions of meaning (or sense), one is meaning proper, the other is determining of reference (p. 59). More precisely, Kripke argues that Frege conflated the question of how the meaning of a word is given or determined with the question of how its reference is determined. The criterial mark of meaning determination, according to Kripke, is a statement of synonymy: if we give the sense of “a” by means of “b”, then the two expressions must be synonymous. The criterial mark of reference-determination is knowledge, typically a priori, of the truth of their identity: If the reference of “a” is given by “b”, then we know a priori that a is b. Kripke then argues that Frege’s conceptions of both meaning-determination and of reference determination were wrong, and proposes an alternative picture of reference determination