On a type-based analysis of feature neutrality and the coordination of unlikes

Abstract

(Ingria 1990)'s claims that both feature neutrality, where a sign acts in a sentence as though it simultaneously had multiple values for a single feature, and the coordination of unlike categories, where the features of two or more conjuncts differ from each other, pose fundamental problems for unification-based theories of grammar do not apply to constraint-based theories like HPSG. New types can be introduced into the hierarchy of appropriate values for any given feature that directly represent neutralizations and coordinations. In this manner, feature neutralization and the coordination of unlikes are seen to be different aspects of the same problem: how to determine the values of a coordinate mother's features from those of its conjuncts.