Pedantry lays out a reasoned defense of prescriptivism, in response to my Field Guide to Prescriptivists. What he has to say is well worth reading. Details aside, I don't disagree with any of it, and it made me realize that my earlier post is easy to misunderstand. I started with the observation that not all advice about usage is bad, while complaining that too much of it is "logically incoherent, factually wrong and promptly disobeyed by the prescriber". The body of my post, after some fluff about bacterial DNA, was an attempt to offer dimensions for characterizing all sorts of arguments about usage, including those I happen to agree with as well as those I don't (and those I'm not sure about).
The dimensions I suggested are orthogonal to questions of fact. My aim in the "Field Guide" post was to clarify the logical form of arguments about usage, as distinct from arguments about the facts of language. An argument of a given form might be valid or invalid on the facts of the case. For example, a surprising number of college students believe that speakers of non-standard varieties are producing a mistaken version of standard forms, exactly like someone who makes mistakes in arithmetic. This is a particularly naive and ignorant form of the "Universal grammar" argument. But not all "Universal grammar" arguments are invalid -- the many overnegation phenomena that we've surveyed are plausibly examples where some commonly-found forms are simply wrong on logical grounds.
Similarly, a factually valid argument can lead to different conclusions depending on language-external judgments. Thus "g-dropping" in many non-standard dialects of English is a residue of an older pattern, keeping separate two morphemes that the standard language has conflated. A g-dropping speaker might decide to conform to the norms of the standard language, or retain the original pattern -- that's exactly like the choice about whether to wear a western string tie or a standard-issue necktie. It's a question of fashion and context, not a question of logic. The implications of tradition are if anything on the side of the non-standard forms, in this case.
Pedantry concludes that "language in its social context has normative elements that we can not ignore. It would be better to embrace them and make our prescriptivism rational instead of leaving it to nonsense merchants in the Times." I agree: the American Heritage Dictionary's usage notes, edited by Geoff Nunberg, are one good model for rational prescriptions about usage; the many normative observations in the Cambridge Grammar of the English Language, co-edited by Geoff Pullum, are another. However, prescriptivism has been so regularly associated with idiocy for so long that you need to choose your words carefully.
Posted by Mark Liberman at April 13, 2004 01:27 PM