The nature of grammaticalization
In this section, which owes much to Croft (2003), we will provide a descriptive overview of the grammaticalisation process. Although the term ‘grammatical isation’ suggests a type of grammatical change, grammaticalisation in fact involves correlated changes in sound, meaning and grammar. In other words, the process of grammaticalisation affects the phonology, morphosyntax and meaning or function of a given symbolic unit. Grammaticalisation can therefore be described as a kind of language change that involves form-meaning reanalysis. Grammaticalisation is essentially the process whereby contentful or lexical constructions (including words) develop grammatical functions, or already grammaticalised constructions evolve further grammatical functions. Grammaticalisation, like many kinds of language change, is unidirectional and cyclic (Croft 2003: 253). It is described as ‘unidirectional’ because the direction of this type of change is from the lexical to the grammatical (from the open class to the closed class), and not vice versa. The cyclic nature of gram maticalisation is evident in the fact that linguistic units enter a language as open-class lexical items, evolve into closed-class items via the process of gram maticalisation, eventually leave the language via a process of loss and are replaced by new open-class items. For example, a common process involves the evolution of a lexical verb meaning ‘want’ or ‘intend’ into a modal auxiliary, then into a bound inflectional (e.g. future) morpheme that may eventually be lost as its function is taken over by a new open-class item.
Another example is provided by Heine et al. (1991) from Yoruba, a Nigerian language that belongs to the Kwa branch of the Niger-Congo language family. The Yoruba verb kpé ‘say’ evolved into a complementiser (1a), was then replaced by another verb wí ‘say’ that was also grammaticalised into a comple mentiser and compounded with kpé (1b), and then this form was lost as a new ‘say’ verb ní emerged (1c). Examples from Lord (1976) cited in Heine et al. (1991: 246–7).
One reason for the cyclic nature of grammaticalisation is the phenomenon of renewal. For example, the English degree modifiers or ‘intensifiers’ (e.g. very in Lily’s knowledge of rocket science can be very intimidating) are particularly prone to renewal. As Hopper and Traugott (2003) observe, at different points over the last 200 years the following degree modifiers have been particularly fashionable: frightfully, terribly, incredibly, really, pretty, truly. Renewal is motivated by the tension that holds between informativeness and routinisation. Routinisation relates to frequency of use and thus predictability: a form becomes highly predictable in linguistic contexts in which it occurs frequently. Because grammaticalisation ensures a more limited distribution of a grammaticalised form, grammaticalised elements tend to become highly predictable. However, predictability entails a reduction in the informational significance of a particular form. This is attested by the phenomenon of phonological attrition, which is the endpoint of morphological fusion and coalescence (discussed below). This process, which eventually results in the complete loss of phonological form, is well attested in the languages of the world (see Hopper and Traugott 2003). Renewal reflects a natural shift towards new forms in order to increase informativeness, by avoiding forms that, as a result of routinisation, have reduced informational significance. This process manifests itself in innovation in language use and contributes to the cyclical nature of the grammaticalisation process.
Grammaticalisation is effected through a shift in the meaning associated with the linguistic unit element from the specific to the schematic. According to the cognitive perspective, the grammaticalised unit takes on meaning associated with the usage event, and is thus a fundamentally usage-based change. The most frequent patterns of grammaticalisation are listed in Table 21.1.
In the next two subsections, we consider in more detail a number of characteristics associated with the grammaticalisation process.
