M. A. K. Halliday
Our text for this symposium is ‘verbal and iconic representations: aesthetic and functional values’. I shall start from verbal representations and functional values; but I shall suggest that functional values may also be aesthetic, and verbal representations may also be iconic. The first part of this chapter will be a general discussion of certain features of the grammar of scientific English. In the second part, I shall focus on one particular text, the final two paragraphs of Darwin’s Origin of Species. I shall assume the concept of register, or functional (diatypic) variation in language. It is convenient to talk of ‘a register’, in the same way that one talks of ‘a dialect’: in reality, of course, dialectal variation is typically continuous, along many dimensions (that is, with many features varying simultaneously), and what we call ‘a dialect’ is a syndrome of variants that tend to co-occur. Those feature combinations that actually do occur—what we recognize as ‘the dialects of English’, for example, or ‘the dialects of Italian’—are only a tiny fraction of the combinations that would be theoretically possible within the given language. Similarly, ‘a register’ is a syndrome, or a cluster of associated variants; and again only a small fraction of the theoretically possible combinations will actually be found to occur. 1
What is the essential difference between dialectal variation and diatypic or register variation? 2 Prototypically, dialects differ in expression; our notion of them is that they are ‘different ways of saying the same thing’. Of course, this is not without exception; dialectal variation arises from either geographical conditions (distance and physical barriers) or social-historical conditions (political, e.g. national boundaries; or hierarchical, e.g. class, caste, age, generation and sex), and, as Hasan has shown (see Hasan, forthcoming) dialects that are primarily social in origin can and do also differ semantically. This is in fact what makes it possible for dialect variation to play such an important part in creating and maintaining (and also in transforming) these hierarchical structures. Nevertheless dialectal variation is primarily variation in expression: in phonology, and in the morphological formations of the grammar.