2.1. Outline of the Swahili noun class system
Swahili, a member of the Sabaki subgroup of Northeast Coast Bantu, has a noun class system that is typical of Bantu languages. All nouns are divided into 11 classes. The class of a noun is signalled by
(a) a pair of prefixes attached to the nominal stem, one for
singular, one for plural;
(b) a characteristic pattern of grammatical agreement, whereby possessive pronouns, demonstratives, verb subject and object prefixes, and other sentence elements coreferential with a noun are assigned a prefix that co-indexes the class of the noun, if it denotes an inanimate object. Sentence elements relating to nouns that denote animate beings are indexed by a special set of "animate concords", regardless of the prefix on the noun.
Table 1 shows the nominal and concordial prefixes associated with the various classes:
Class Nominal Prefix Adjectival Pfx Pronominal Pfx (tradi- (affixed to (affixed to (affixed to tional `fixed class' `variable V stems as Bantu stems class'stems) Subj/Obj; numbering) to Dem.Pro., Poss.Pro.&c.) 1 m- m- a-/m-; yu-; w-;ye- (depends on stem) 2 wa- wa- wa- 3 m- m- u- 4 mi- mi- i- 5 zero or ji- zero or ji- li- 6 ma- ma- ya- 7 ki- ki- ki- 8 vi- vi- vi- 9 zero or n- zero or n- i- 10 zero or n- zero or n- zi- 11/14 u- m- u-
Inspection of Table 1 shows that noun class cannot be determined solely from the form of the noun: the prefixes for Classes 1 and 3 (m- in both cases) are homonymous; this is also often true of Classes 9, 10, and 5, where the noun may have no prefix at all. The agreement prefixes also show some homonymy. Therefore the definition of `noun class' in Swahili normally involves reference both to the prefix on the noun (if there is one) and to the pattern of grammatical agreement.
2.2. Earlier treatments of the noun classes
As mentioned above, noun classes in Bantu languages are defined in part by the formal marking of the noun (its class prefix), and in part by the association between a set of nouns on the one hand, and a set of `agreement markers' affixed to possessive pronouns, verb stems, etc., on the other. Although there is a wide range of opinions about whether the noun classes in Swahili and other Bantu languages have semantic content, there is great uniformity on the treatment of grammatical agreement. Agreement is assumed to be a purely syntactic phenomenon, in which the grammatical properties of one element in the sentence (the agreeing element, or `target', in the terminology of Corbett 1991) are determined by those of another element (the `controller', in this case the noun). In other words, it is assumed that `agreement' morphology contributes no independent semantic content to the message being communicated, but is merely a mechanical copying of features of the `controller' onto the `target'. Implicit in this view is the further assumption that `controllers', such as noun stems, `have' fixed grammatical properties (e.g. membership in a particular noun class); without this assumption one could hardly speak of copying features from the noun to, say, a coreferential demonstrative pronoun.
Given this prevailing view of concord, the question of meaningfulness of the noun classes in Bantu languages has only been raised with respect to the prefixes attached to noun stems. The question that has been addressed is, can any regular semantic principles be identified to explain the assignment of noun stems to classes? Answers to this question, perhaps predictably, range from no to yes, but the majority opinion lies somewhere in between.
Perhaps the most extreme position on the `no' side is that of Irvine Richardson (1967:378), whose assertion that `...it is impossible to prove conclusively by any reputable methodology that nominal classification in Proto-Bantu was indeed widely based on conceptual implication...' is widely quoted, especially by those who disagree with it. At the other end of the spectrum are those who have tried to define each noun class in terms of a single abstract meaning, such as Denny and Creider's (1976) analysis of Proto-Bantu, and Zawawi's (1979) analysis of noun classes in Swahili.
Denny and Creider argue that Proto-Bantu had two subsystems of categorization, with partially overlapping morphology, one for count nouns and one for mass nouns. The count noun categories are further subdivided into `kind' classes, that identify objects as animate vs. artifact, and `spatial configuration' classes, that subclassify objects according to shape. The mass noun categories make a distinction between `cohesive' (substances that stick together) and `dispersive' (substances composed of dry particles that are readily dispersed).
In the same spirit, though differing in content, Zawawi (1979) assigns a single invariant meaning to each noun class prefix in Swahili. Zawawi's analysis is innovative: she abandons the traditional criteria for definition of the classes, pointing out correctly that they are often inconsistent, and even groups together prefixes traditionally treated as homonyms. According to her analysis, the singular classes subclassify nouns as `substance of life' (m-, traditionally divided into Classes 1 and 3), `substance of abstractness' (u-, traditionally defined as a merger of Classes 11 and 14), `comparison of size or manner' (ki-, Class 7), `intensification' (zero ~ ji-, Class 5), `large' (ba-, not a traditional Bantu class), and a residual `catch-all' category (zero ~ n-, Classes 9/10).
Unfortunately, analyses of the noun classes in terms of invariant meaning have failed to convince the skeptics, because there are always some examples that conflict with the invariant meanings that are posited. For instance, Denny and Creider's definition of Proto-Bantu Class 3 as `solid, extended in one dimension' does not seem to cover terms like *-dImu `ancestral spirit', *-tIma `heart', *-yedI `moon', *-gUba `bellows', *-dIgo `load', *-yInci `daylight', etc. And Zawawi's definition of m- as `substance of life, singular' does not cover terms like mkufu `metal chain', mji `town', mfumbi `irrigation ditch', mlia `stripe', deverbal nouns, etc.
The middle-of-the-road position on the semantics of the noun classes is to divide the noun classes into two subsets: a `derived' set of classes, assumed to be meaningful, to which noun stems from any class can be freely assigned with predictable effects on meaning, and an `inherent' set of classes, whose membership is largely arbitrary. Formally, these sets overlap: the same morphology is used for both `inherent' and `derived' class. The `derived' classes include the diminutive classes (with ki-/vi- prefixes, homonymous with the prefixes of Classes 7/8) and the augmentative classes (with zero/ma- prefixes, homonymous with the prefixes of Classes 5/6). With respect to the `inherent' classes, it is usually argued that although some semantic generalizations can be made about the groupings of nouns into classes, there is also a great deal of arbitrariness. It is often surmised that the present, disorganized system is a breakdown of an earlier, more coherent system assumed to have existed in the ancestor language. Examples of studies employing the `inherent/derived' distinction are Givon (1972), for ChiBemba; Heine (1982), who uses the terms `free' vs. `fixed' gender; Reynolds (1989), Reynolds and Eastman (1989), and Nurse and Hinnebusch (1993) for Swahili.
Although it is useful to distinguish between productive and non-productive processes of noun formation, the `inherent/derived' distinction ignores the question whether there are any semantic regularities in `inherent' classes, and also ignores semantic relationships, if any, between `inherent' and `derived' class markers. Rarely is any attempt made to connect the various groupings of nouns in a given class with one another, to investigate systematic relationships among different classes, or to explain the exceptions to the generalizations (such as names of animals that are are not in the `animal' class). Also, the claim that the modern languages represent a breakdown of an earlier, more coherent system that used to exist in the ancestor language is basically a myth. The Proto-Bantu noun class system also had many apparent anomalies-- if it didn't, there would be no controversy about whether the Proto-Bantu noun classes were meaningful (see also Herbert 1985). In fact, claims about a mythical, semantically transparent system assumed to have existed in an ancestor language are commonplace in discussions of noun categorization, not only in Bantu (cf. Meillet 1923 on gender in Indo-European), yet no modern noun class language is attested with such a transparent system. It seems implausible to attribute a property to an ancestral language that is not found in any language of which we have direct knowledge. But if noun class systems are so full of anomalies, why do they persist for so long essentially intact (in the case of Bantu, some 3000 years or more)?
The problem seems to lie not with the languages, but with the assumptions about the nature of linguistic categorization that are brought to bear on this question. It seems to be assumed that either noun class semantics must be defined in terms of a set of common properties shared by all nouns in a given class, or one must abandon the search for semantic coherence and settle for a heterogeneous list. As pointed out by Lakoff (1987), this assumption is based on a view of linguistic categories as equivalent to sets in Aristotelian logic, which must be defined in terms of a set of necessary and sufficient conditions for membership. This view of linguistic categorization has been widely challenged in recent years, especially from the point of view of Cognitive Grammar (cf. Lakoff 1987; Langacker 1987, 1990; Rudzka-Ostyn 1988). It has been argued that membership in a given linguistic category (for example, a noun class) may be based on multiple criteria, including `family resemblances', metaphor, and metonymy, and that linguistic categories may exhibit an internal structure in which some members of the category are more central, or prototypical, and others are more peripheral. Although work within Cognitive Grammar has tended to concentrate on the semantics of individual lexical items, there are some detailed and illuminating studies of noun categorization that make use of similar insights: the work of Zubin and Koepcke on gender in German (Zubin and Koepcke 1986a, 1986b) and the work of Spitulnik on noun classes in ChiBemba (Spitulnik 1987, 1989).
In sum, rather than treating noun class systems as degenerate reflections of an earlier, vanished coherence, we should broaden our conception of `coherence'. From a cognitive-semantic viewpoint even the synchronic systems of the modern languages can be shown to make sense.