Sociolinguistic : The Scientific Investigation of Language

The scientific study of  language, it uses, and the linguistics norms that people observe poses a number of problems. Such study must go a long way beyond merely devising schemes for classifying the various bits and pieces of linguistic data you might happen to observe. That would be a rather uninteresting activity, a kind of butterfly collecting. A more profound kind of theorizing is called for : some attempt to arrive at an understanding of the general principles of organization that surely must exist in both language and the uses of language. It just such an attempt that led Saussure (1959) to distinguish between langue (group knowledge of language) and parole (individual use of language ; bloom field (1933) to stress the importance of contrastive distribution (since pin and bin are different word in English,/p/ and /b/ must be contrastive units in the structure of English; Pike (1967) to distinguish between emic and etic features in language are contrastive, therefore emic, unit, but the two pronunciation of p in pin and spin are not contrastive, therefore etc); and Sapir (1921) and much later, Chomsky (1965) to stress the distinction between the surface characteristic of utterances and the deep realities of linguistic from behind these surface characteristic. A major current linguistic concern is with matters such a language universals (i.e, the essential properties and various typologies of languages learnable but humans ( but not non-humans) and with the condition that govern such matters as linguistic change.
There is not just one way to do linguistic, although it is true to say that some linguistic occasionally behave as though their way is the only way. It is actually quite possible for two linguists to adopt almost entirely different approaches to both language and linguistic  theorizing in their work while still doing something that many consider to genuine linguistic. Perhaps nowhere can such differences of approach be better observed than in attempts to study the relationship of language to society. Such attempts cover a very wide range of issues and reveal the diversity of approaches ; different theories about what language is; different views of what constitute the data that are relevant to a specific issue; different formulations of research problems; different conceptions of what are good answer in terms of statistical evidence, the significance or interest of certain findings and the generalize ability  of conclusions ; and different interpretation of both the theoretical and real word consequences of particular pieces of research, i.e. what they tell us about the nature of language or indicate we might do to change or improve the human condition.
What we will see the, time after time, is a sociolinguistic without a single unifying, theme - expect that it is about the relationship of language to society and without a single unifying approach. That view should not necessarily disturb us, if for no other reason than that the parent disciplines , linguistics and sociology may not be much better off in this respect : internal controversy rather than widespread agreement seems to be the norm in both. Moreover, there is a little reason to suppose that work done with single theme and approach would encompass all that we would want to do it: it would do no more than illuminate part of the various problems that exist and do so in its own peculiar light. In the current state of our knowledge we can scarcely afford to choose too readily such a limited focus for our investigations.