Directionality and (Un)natural Classes in Syncretism

Syncretism, where a single form corresponds to multiple morphosyntactic functions, is pervasive in languages with inflectional morphology. Its interpretation highlights the contrast between different views of the status of morphology. For some, morphology lacks independent structure, and syncretism reflects the internal structure of morphosyntactic features. For others, morphological structure is autonomous, and syncretism provides direct evidence of this. In this article, I discuss two phenomena which argue for the second view. Directional effects and unnatural classes of values resist attempts to reduce them to epiphenomena of more general rule types, and require purely morphological devices for their expressio