Thomas Ede Zimmermann (Frankfurt) gives a talk at the MCMP Colloquium (25 June, 2015) titled "Fregean Compositionality". Abstract: The distinction between transparent and opaque contexts has always played a major rôle in theories of linguistic semantics, though it has undergone a number of reformulations and precisifications since its origins in Frege’s classical substitution arguments. Most dramatically, the unfathomable distinction between Sinn and Bedeutung has been recast in more perspicuous set-theoretic terms, trading Frege’s senses for Carnap’s intensions and identifying functions with their courses of values. Still, at least part of the Fregean architecture has survived all these transformations. In particular, (i) the strategy of treating extensionality as the default case of semantic composition and invoking intensions only when need be, has become part of most common approaches to the syntax-semantics interface. On the other hand, (ii) Frege’s apparent commitment to a hierarchy of senses in the analysis of iterated opacity has been discarded for its alleged lack of cogency and coherence. In the talk I will take a closer look at both aspects of the Fregean architecture within the standard possible worlds framework of Montague’s Universal Grammar. Concerning (i), it will be argued that the Fregean strategy results in an interpretation of intensional constructions (i.e., opaque contexts) that goes beyond mere intensional compositionality in that it imposes a certain kind of uniformity on the pertinent semantic combinations. As to (ii), it will be shown how a hierarchy of intensions may help restoring compositionality when extensional and intensional scope effects appear to be out of tune. The historical background notwithstanding, the the talk will take systematic perspective, aiming at a better understanding and possible improvement of compositionality in possible worlds semantics.