Morphology, divided and conquered?

Concentrating on the taxonomy of grammatical morphemes, this study shows that traditional definitions of inflectional vs. derivational morphemes do not pass more rigorous testing, although they probably reflect instinctive distinctions present in a natural language system. The authors propose to define the distinctions by referring to derivational stages, namely by distinguishing levels of insertion for morphemes. Most of what is usually classified as derivational morphology and subject to the Right Hand Head Rule are morphemes which enter derivations in narrow syntax. As such, they conform to what is here termed a Logical Form Interpretation Condition, which allows only one syntactic feature per morpheme. On the other hand, morphemes such as agreements are not subject to the Right Hand Head Rule and result from post-syntactic insertion and exhibit cross-classification. The authors propose that the source of these bound inflections is the process of Alternative Realisation. They argue that their new distinction between derivational and inflectional morphology correlates with testable semantic, phonetic and syntactic properties and that in terms of these properties, both are necessary parts of an adequate formal linguistic framework.