Focussing on the semantics of attitude reports, the paper compares two classic approaches to intensionality. The first one, going back to Frege, treats extensional compositionality as the default and employs constituents’ intensions whenever their extensions defy substitution. The second one, suggested by Russell, does with one layer of semantic values and seeks to reduce all intensionality to propositional embedding, thus giving rise to the doctrine of propositionalism. Both approaches can be cast in a type-logical framework, whence the Russellian strategy comes out as a restricted version of the Fregean one. Thus, as Montague argued, the choice between them appears to be a matter of empirical coverage, with Partee’s puzzle (about rising temperatures) as a principal witness. However, a theorem due to Kaplan reveals that Fregean analysis can be mimicked within the Russellian framework by way of a coding procedure (called Russelling). This still leaves open the possibility that the Fregean approach to intensionality is preferrable on meta-theoretic grounds like simplicity or cognitive relevance. The decision between the two approaches thus calls for further descriptive and empirical evidence.
Thomas Ede Zimmermann (Fri,) studied this question.