Vagueness and Grammar: The Semantics of Relative and Absolute Gradable Adjectives

This paper investigates the way that grammatical (lexical semantic) features of linguistic expressions influence vagueness, focusing on the interpretation of the positive (unmarked) form of gradable adjectives. I begin by developing a semantic analysis of the positive form of `relative' gradable adjectives, in which vagueness derives from the truth conditions of the predicate, which require an object to possess a contextually significant degree of the relevant property (as in Graff 2000). The analysis expands on previous proposals both in further motivating a semantic approach to the vagueness of the positive form and in precisely identifying and characterizing the division of labor between compositional and context dependent elements in its interpretation. I then introduce a challenge to the analysis from the class of `absolute' gradable adjectives: adjectives that are demonstrably gradable, but which have positive forms that relate objects to maximal or minimal degrees, and do not give rise to vagueness. I argue that the truth conditional difference between relative and absolute adjectives in the positive form stems from the interaction of lexical semantic properties of gradable adjectives and a general constraint on interpretive economy that requires the meaning of a constituent to be computed strictly on the basis of the conventional meanings of its subconstituents to the extent possible, allowing for context dependent truth conditions only as a last resort.