In this chapter …

In the last chapter, and as part of some formal work we completed on the representation and transcription of long vowels, we began to notice some details of the present-day variation that exists in the system of English long vowels. In this chapter we're going to say more about variation, and put ‘variation’ into a conceptual framework that will allow us to distinguish present-day variation (which we'll call synchronic variation) from those variations that seem clearly to be the products of historical change (diachronic variation). Although this isn't a book about diachronic phonology, we'll see that any account of synchronic phonology would do well to be aware of the history that underlies the system. (Further, many students simply are curious about, and like to know, how and perhaps even why their own phonology took shape in the way it did.) In terms of diachronic phonology we can't do everything in a book of this kind, of course, but we can analyse key processes and structures which play large parts in any reconstruction of how phonological systems evolve. Those processes and features we'll look at here are splits and mergers (10.2) together with vowel (a)symmetries (10.3). In 10.3 we'll begin to say something about what many handbooks on the history of English call the Great Vowel Shift, and will also notice that the concepts of symmetry and (chain-)shift might usefully be invoked in the context of analysing one recent synchronic change in RP (from /æ/ to /a/ in words such as cat) – see section 10.4.