Comparison of the three approaches: be going to
We conclude our discussion of the three theoretical approaches to grammaticalisation presented in this chapter with a brief comparison of how each approach accounts for the be going to construction. As we saw in section 21.2, the metaphorical extension approach analyses the shift from ALLATIVE to FUTURE in terms of metaphorical extension from the more concrete domain of SPACE to the more abstract domain of TIME. Because the be going to construction exhibits polysemy, which is potentially problematic for a metaphorical extension account, the analysis developed by Heine et al. (1991) also takes into account the role of discourse context, which gives rise to context-induced rein terpretations based on metonymy or experiential correlation, for example between motion and intention: recall our discussion of example (8).
In contrast, we saw in section 21.3 that Invited Inferencing Theory (Traugott and Dasher 2002) rejects the metaphorical extension account, and analyse the be going to construction in terms of a shift from a construction encoding a speaker-external event towards a construction encoding speaker perspective relative to TIME and SPACE. According to this theory, the ALLATIVE sense encodes a concrete and objective event, while the FUTURE sense relates to the speaker’s location in TIME and is therefore more subjective: recall example (15).
Finally, we saw in section 21.4 that the subjectification approach developed by Langacker (1999b) analyses the evolution of the ALLATIVE into the FUTURE sense in terms of the nature of the conceptual processes that underlie each interpretation. While the ALLATIVE sense involves the conceptualiser scanning actual physical motion through space, objective construal is salient and subjective construal remains backgrounded. In contrast, the FUTURE sense lacks physical motion and therefore objective construal is attenuated, which enables subjective construal to become salient.
In many ways, the fully usage-based character of the theory proposed by Traugott and Dasher, which views metaphor as epiphenomenal, is in keeping with some of the most recent trends within cognitive linguistics, which focus increasingly upon ‘bottom-up’ or usage-based explanations of ‘dynamic’ aspects of language use, rather than upon ‘top-down’ or structural explanations that are characteristic of conceptual metaphor theory. As we will briefly see in Chapter 23, the changing status of conceptual metaphor in grammaticalisation theory has parallels in the recent movement within cognitive semantics to question the status of conceptual metaphor as an explanatory construct. This is evident in research on conceptual blending (e.g. Turner and Fauconnier 1995, and indeed to some extent Grady et al. 1999); in research on cognitive lexical semantics (e.g. Evans 2004a); and in research on conceptual projection (Zinken et al.forthcoming). Moreover, research outside cognitive linguistics (e.g. Stern 2000) is increasingly critical of the absence of a serious account of context and use in conceptual metaphor theory. As we saw in our discussion of Heine et al.’s ‘metaphor’ account of grammaticalisation, a descriptively adequate account of grammaticalisation cannot ignore the context of language use, which, at least in part, contributes to the process of grammaticalisation.
While not strictly an account of grammaticalisation per se, which is a historical and usage-based phenomenon, Langacker’s account represents a serious attempt to model the kinds of mental processes that result in the form-meaning reanalysis characteristic of grammaticalisation. It follows that Langacker’s account complements (rather than competes with) the usage-based accounts proposed by Heine et al. and by Traugott and Dasher.
