A modular approach to intensionality

This paper introduces a procedure that takes a simple version of extensional semantics and generates from it an equivalent possible-world semantics that is suitable for treating intensional phenomena in natural language. This process of intensionalization allows to treat intensional phenomena as stemming exclusively from the lexical meaning of words like believe, need or fake. We illustrate the proposed intensionalization technique using an extensional toy fragment. This fragment is used to show that independently motivated extensional mechanisms for scope shifting and verb-object composition, once properly intensionalized, are strictly speaking responsible for certain intensional effects, including de dicto/de re ambiguities and coordinations containing intensional transitive verbs. While such extensional-intensional relations have often been assumed in the literature, the present paper offers a formal sense for this claim, facilitating the dissociation between extensional semantics and intensional semantics.