Descriptive or prescriptive?

You have learned that linguists see their task as describing language and attempting to find explanations for real language data, rather than telling people how they should speak: linguistics is descriptive, not prescriptive. In this connection we saw that there are two kinds of rule. It’s a descriptive syntactic rule of English that the house is grammatical, but not *house the¹ (a structure which is fine in Swedish and Bulgarian), because no English speaker would naturally say this. Similarly it’s a descriptive rule of English phonology that no word can begin with the sequence *vdr-, which is a perfectly acceptable word-initial sequence in Russian.

Rules of the ‘don’t split infinitives’ kind, on the other hand, are prescriptive, in that they set out what purists think speakers ought to do. Prescriptive rules are generally associated with the usage of a dominant or prestige group, and are generally reinforced by the formal education system: that they need to be, of course, is a sure indication that they are often transgressed. A linguist’s first task is to describe the rules that a native speaker unconsciously obeys, whether or not these correspond to those of standard usage. In doing so, linguists accord primacy to speech because children acquire language through hearing and speaking before learning to read and write, and because conventional writing systems are at best an inconsistent and poor reflection of that speech. These two principles are fundamental to linguistics, and if you’ve grasped them, congratulations! You’re starting to think like a linguist.