The Unabridged Feature Classes in Phonology

This paper argues for a particular understanding of feature class behavior the recurrent patterning together of certain phonological features, such as place of articulation and laryngeal features. The proposals build on the well known work of Feature Geometry in assuming the importance of feature classes in phonology, but differ in that features of a class are targeted directly and invidually by constraints (or rules), even when a feature class such as 'Place' is mentioned. Further, constraints mentioning feature classes are gradiently violable. Evidence for this view of feature classes comes from two sources. First, assimilation involving feature classes is sometimes only partially successful; an adequate understanding of such cases requires the proposed view of feature classes. Second, there are broad categories of feature class generalization that require it, including dissimilatory effects usually handled by the Obligatory Contour Principle. Overall, the proposals broaden the explanatory potential of the feature class idea due to Feature Geometry. At a more general level, the results here suggest that linguistic representations sometimes need to be reconsidered in the context of Optimality Theory (Prince and Smolensky 1993), since they can effectively function as inviolable constraints and so hinder our understanding of the more subtle kind of phenomena revealed by analyses employing gradiently violable constraints. 1. Feature classes. It is a familiar observation that certain phonological features pattern together recurrently across languages in phenomena such as assimilation, dissimilation, and reduction. Perhaps the phenomenon most frequently cited as an example of this is nasal place assimilation. In Kpelle (a Mande language of West Africa), for example, nasal place assimilation occurs as in (1). (1) Kpelle nasal place assimilation [m]bolu 'my back' [ ]g@@ 'my foot' [f]vela 'my wages' [ 0m]g0bi 'myself' [n]duH 'my front' Nasal place assimilation as in Kpelle is very common, though languages differ in the precise conditions they place on it. Of interest here is the fact that it is frequently enforced over all places of articulation, as in the Kpelle case, and not over just one place of articulation; further, the rule affects only place of articulation features, rather than any random subset of phonological features. As the familiarity of the term 'place assimilation' implies, there seems to be a recurrent, unitary generalization covering all and only the places features. How should this generalization about place features be understood? A well-known answer to this question is provided by Feature Geometry (Mohanan 1983, Mascaró 1983, Clements 1985, Sagey 1986, McCarthy 1988, and much subsequent work). Feature Geometry posits that the relevant features are grouped together under a node Place in a universal autosegmental representation; rules or constraints target this node directly, and thereby affect all of the place features indirectly. For the case at hand, suppose a constraint requires that a nasal consonant share Place with a following obstruent, making the partial representation in (2)a well formed and that in (2)b ill formed. The indirect result of this will be that the two consonants share whatever features Place dominates, as in the representative examples of (2)c. In this way Feature Geometry provides a simple, unitary characterization of nasal place assimilation.