 Extra-linguistic context determines what way of grasping (what Crimmins and Perry call an idea) an utterance of a propositional attitude ascribing sentence makes implicit reference to. (On the most plausible version of the view, a type of way of grasping, instead of a token way of grasping, that is implicitly referred to.) The expressions themselves (and not just their referents or semantic contents) are, however, typically relevant to what way of grasping is implicitly referred to. So, although substitution of co-referring names does not affect the proposition the propositional attitude ascribing sentence claims the target of the report to have an attitude towards, as it does on the Fregean view, in some cases it affects what way of grasping is implicitly referred to and hence is capable of affecting truth-value of a propositional attitude ascribing sentence. (Some call views of this kind “hidden-indexical theories” because the sentence does not contain a syntactic element that explicitly refers to a way of thinking. See Schiffer 1992, p. 503. Schiffer offered a version of this view in his 1977, as did Brian Loar 1972. Greg Fitch also presented a similar view in his 1984 and 1987. We focus on Crimmins and Perry’s version, which is the most fully developed version of the view.)