Type Shifting with Semantic Features: A Unified Perspective

Since their introduction by Partee and Rooth (1983) into linguistic theory, type shifting principles have been extensively employed in various linguistic domains, including nominal predicates (Partee 1987), kind denoting NPs (Chierchia 1998), interrogatives (Groenendijk and Stokhof 1989), scrambled definites (De Hoop and Van der Does 1998) and plurals (Winter 2001,2002). Most of the accounts that use type shifting principles employ them as “last resort” mechanisms, which apply only when other compositional mechanisms fail. This failure is often sloppily referred to as type mismatch. The motivation for introducing type mismatch into the compositional mechanism is twofold: on the one hand it allows lexical items to be assigned the minimal types that are needed for describing their denotation; on the other hand, it has been argued that the “last resort” strategy of type shifting prevents derivation of undesired meanings. The first goal of this paper is to define a simple notion of type mismatch, which will rather closely follow Partee and Rooth’s original proposal but will be expressed within more familiar terms of categorial semantics. After introducing this implementation of traditional type mismatch, it will be argued that in fact, it covers only one possible kind of trigger for type shifting principles. Partee and Rooth’s notion of mismatch is “external” in that the type of an expression is changed only when it combines with another type to which it cannot compose using the “normal” compositional mechanism. It will be argued that, within an appropriate type system, another notion of mismatch is also useful. This is the kind of mismatch in which the semantic type of an expression does not match its syntactic category. Two such cases will be explored: mismatch between morpho-syntactic number (singular or plural) and semantic number (a denotation ranging over atoms or sets), and mismatch between syntactic category (noun, DP, adjective etc.) and semantic role (predicate, quantifier, predicate modifier etc.). Both ”external” and ”internal” mismatch, which were proposed as triggers for type shifting in Winter (2001), will be formalized in one system where the definition of types matches more closely natural linguistic notions of semantic roles and semantic number.