Word-class-changing inflection and morphological theory

One of the most common claims made about the difference between inflection and derivation in the morphological literature is that derivational affixes change the word-class of their base, while inflectional affixes do not change the word-class. In this paper I argue that this view is wrong, and that important insights about the nature of inflection and derivation are lost if word-class-changing inflection is not recognized. In §2, I present a number of examples of word-class-changing inflection, and in §3–5 I discuss several potential objections to my analysis. I show that the cases in question can be regarded neither as word-class-changing derivation (§3–4) nor as non-word-class-changing inflection (§5), and that a description in terms of feature neutralization is not a general solution (§6). In §7 I argue that to account for the syntactic properties of words, two types of word-class have to be distinguished: lexeme word-class and word-form word-class. §8 discusses some problems that arise in the formal representation of this proposal in constituent-structure trees and observes that Tesniere’s dependency grammar provides an interesting perspective. Finally, §9 discusses the universal correlation between inflection and preservation of internal syntax, and derivation and the non-preservation of internal syntax.