| ROA: | 270 |
|---|---|
| Title: | Yoruba vowel patterns: deriving asymmetries by the tension between opposing constraints |
| Authors: | Douglas Pulleyblank |
| Comment: | |
| Length: | 24 |
| Abstract: | Yoruba vowel patterns: deriving asymmetries by the tension between opposing constraints Douglas Pulleyblank University of British Columbia This paper re-examines a class of pervasive asymmetric properties in the vowel system of Yoruba. Pulleyblank (1988) argues that high vowels in general and [i] in particular exhibit a special array of properties. For example, certain rules of assimilation and deletion are triggered by all vowels except high vowels. Other rules of assimilation target only high vowels. In loan vocabulary, [i] is the epenthetic vowel in non- assimilatory contexts. In Yoruba, as in numerous other cases in the literature, the recurrence of a particular feature as a conditioning or nonconditioning factor in various processes can be interpreted as an argument in favour of underspecified representations (Pulleyblank 1988). If [-high], [+back], etc. are structurally present in Yoruba vowels, but [+high] and [-back] are not, then the cited facts receive an explanation. When assimilation fails to be triggered by [i], this is due to the absence of features specified for that vowel. When only [i] is targeted by a rule, this is because the rule is structure-building, not structure-changing. The epenthesis of [i] is analysed as syllabically- motivated insertion of a featureless prosodic vowel. While resolving a number of problems, an underspecified approach raises others. Clements & Sonaiya (1990) argue that a rule of L Nasalisation makes crucial reference to [+high], as does a Morpheme Structure Constraint; Akinlabi (1993) makes a similar argument for a rule of r-deletion. Such patterns that reference [+high] are incompatible with an underspecified analysis of the Yoruba vowel system. Note in particular that certain rules requiring reference to [+high] apply very early (e.g. as a morpheme structure condition) while certain rules behaving asymmetrically apply very late (e.g. a rule of vowel deletion that crosses word boundaries). The apparent conflict in behaviour cannot be resolved, therefore, by assuming an early stage of underspecification followed by a subsequent stage of more complete specification. Of particular interest to the treatment of asymmetric phonological behaviour, both the paper by Clements & Sonaiya and the paper by Akinlabi reinforce the asymmetric nature of high vowels, each presenting additional data of a special asymmetric nature. Hence even though the underspecification approach appears to fail, if we accept their arguments then it becomes even more important therefore to find a theoretical account that can satisfactorily account for the asymmetries in the Yoruba vowel system. This paper discusses three possible analyses for Yoruba. First, it lays out the possibility that there are no special asymmetries at all, that the particular properties of any individual construction are due to idiosyncratic properties of individual rules. Second it examines the possibility that asymmetries are significant and due to a structural property such as underspecification. Third, it explores the possibility that asymmetric behaviour results from the relative ranking of constraints. That is, the special properties of high vowels result not from structural encoding, but from the ranking of constraints on high vowels above and below constraints implicated in particular constructions. It is shown that both rule-governed and underspecified accounts require special stipulations of an ad hoc nature as additional constructions are considered, where the constraint-based approach does not. The general conclusion is that a constraint-based approach resolves the problems raised by the analyses of Clements & Sonaiya and Akinlabi, as well as other problems intrinsic to the proposal of underspecification. The paper therefore constitutes an argument in favour of the encoding of asymmetries in a constraint grammar rather than in elaborated structures. In developing the treatment of asymmetric behaviour, harmonically ranked sonority constraints play a central role. The paper argues that such reference to sonority must be encoded directly into the expression of the faithfulness constraints, rather than through an independent set of well-formedness conditions. That is, the paper argues for the encoding of "sonority as faithfulness". |
| Type: | Paper/tech report |
| Area/Keywords: | |
| Article: | Version 1 |