ORLAPUBS P. L47: WHAT LANGUAGE IS vs. HOW IT IS USED

WHAT LANGUAGE IS AND HOW IT IS USED:
MYTHS HELD BY MOST SOCIOLINGUISTS
AND DIALECTOLOGISTS

Comments made here will refer to natural language that have grown up among humans, or even been invented along the lines of such was well, as scientific artificial languages (e.g. modal logic)--but not vague entities like "the language of art," etc.

A language has got to have a GRAMMAR that enables one to predict how to make new expressions--those which one has never yet heard or read--that conform to the language SYSTEM in question. The job of linguistics is to offer an explanatory- predictive analysis or theory of a language system in terms that are not ad hoc but part of known of provable language universals--universals of human languages, when a human language is what is being analysed.

How language functions--what it is used for--is a separate question. A psychological real grammar includes all of the different styles one has at one's disposal in a given language as well as the age, class, and regional variants of that language. Note that one's style differences overlap many of the age or class or regional differences; e.g. a more formal style may be less formal in the usage of one's grandparents, and a more informal style may be formal among one's grandchildren's. What is more-formal for a lower class will be less formal for a higher class in the same region and age group, and what is less-formal for a higher class in the same region and the same age group will likely be more formal for a lower-class--if it has the "lect" at all. A known exception discovered by Wm. Labov is that formal style of the second-highest class will be more formal than that of the highest class--because of emulation and over-correction.
These differences are (i) time based and (ii) implicational. The first item means that less-formal lects of younger speakers will be later (barring a re-ordering of a rule to a less-marked order or a reversal in a marked category or marked context) later-developed than those that are more formal or restricted to older speakers. The second item means that (barring a re-ordering of a rule to a less-marked order or a reversal in a marked category or marked context) the later items will imply the earlier ones, including many of its rules but not seldom in a less-restricted form (i.e. the input, output, or environment may be more general). The grammatical system includes all of the rules in their applicational ordering and some device to indicate the implicational ordering; it goes without saying or needing to be indicated that a more general form of an input, environment, or sequenced output of a rule is implied by a less general form of that part of a rule. The more restricted input, environment, or less-sequenced output will have more features; the loss of features automatically makes a rule more general and, where the result would be linguistically possible, is taken as a potential development of a less-general or more-restricted rule-part.