Description and explanation in morphophonology: the case of Japanese verb inflection

要旨

The suffixal alternations of Japanese verbal inflection have been analyzed in at least four distinct ways in the literature. In this paper, working in the context of a general model of the inferential relation between synchrony and diachrony in inflectional morphophonology, I compute the predictions for potential change for three analyses of those alternations and show that only one set of predictions is consistent with the ongoing changes evident in a nationwide survey of inflection. I conclude that the analysis generating the correct predictions is the unique descriptively adequate analysis of the system of alternations in question. With regard to the explanatory principles governing the choice of that analysis from the set of observationally adequate alternatives, I show that the Japanese case counterexemplifies a wide range of proposals that have been made about the operation of morphophonological analysis and change and propose that the choice of both base forms and rules is due to a principle of Generalized Type Frequency. Among the general themes of the paper are the grammatical reality of language-specific phonological rules, the relevance of analogical processes to synchronic description and explanation, and the limited role played in morphophonological analysis by global considerations of predictability.