 There is a sizable literature on the semantics of  propositional attitude reports  (see entry). Some think that considerations like this show that there are no genuine synonyms in natural languages. If so, compositionality (at least the language-bound version) is of course vacuously true. Some deny the intuition that (7) and (8) may differ in truth-conditions and seek explanations for the contrary appearance in terms of  implicature.[22]  Some give up the letter of compositionality but still provide recursive semantic  clauses.[23]  And some preserve compositionality by postulating a hidden indexical associated with ‘believe’ (for example, Richard 1990, Crimmins &amp; Perry 1989, and Crimmins 1992).