A fellow editor has reported an exchange with someone who insists that “common usage shouldn’t trump actual rules.”
What this person doesn’t understand is that common usage makes the rules. Common usage between Norman overlords and English peasants over centuries is what turned Anglo-Saxon into English.
Common usage is how semantic shift occurs, which is why you encounter terrible in meanings other than “causing great fear and alarm.”
Common usage is the reason that British and U.S. English often diverge.
And really, what do you suppose he means by “actual rules”?
Eighteenth- and nineteenth-century grammarians, instructing the rising middle class in the prestige dialect of commerce, law, and government, looked to Latin as a model, because Latin and Greek were the prestige language they had learned in school. Some of the things they attempted to graft onto English—no split infinitives, no prepositions at the end of sentences—never really took, except in schoolrooms.
So I am going to republish here material from a previous post about what are rules in English grammar and what are not:
Unnoticed rules: Unless you are learning English as a second language as an adult, there is a whole network of subterranean rules of grammar that most native speakers never think about. The order of adjectives is an example.
Explicit rules: There are many of them, but they are often complex, with many exceptions and variations. Try to explain subject-verb agreement to a non-native speaker, making clear how “Ham and eggs are my favorite breakfast combination” and “Ham and eggs does not constitute a healthy breakfast” are both grammatically acceptable.
Conventions: Writers in the eighteenth century regularly inserted a comma between the subject and verb in a sentence. We don’t any longer. English orthography is a swamp of maddening conventions. And they, too, are subject to change; we no longer write to-day and to-morrow.
Superstitions: The things Arnold Zwicky calls “zombie rules”—no stranded prepositions, no split infinitives, none always a singular—have been exploded and rejected, not only by the descriptivist tribe, but by a multitude of prescriptivists. And yet, given a ghastly immortality by generations of defective schoolroom teaching, they persist against all reason.
Shibboleths: There are many usages that are not wrong but which people seeking advantage over their fellows preen themselves on avoiding. Ain’t, I suppose, is the classic example, hopefully a comparatively recent addition—though the peevers maintain a vast and ever-increasing store.
House style: These are the narrow conventions that individual publications or publishing houses insist on. They are very specific for legal, medical, scientific, and technical publications. And, of course, there are those sad souls on copy desks who think that the Associated Press Stylebook belongs on the shelf with the statutes of Hammurabi and Justinian.
Individual aesthetic preferences: Everyone has them, and tinpot authorities—managing editors, self-appointed Guardians of the Language, that ilk—love to impose them on the weak and unwary.
Over time, all of this is up for grabs. Oh, dictionaries, style guides, and universal public education tend to put a brake on language change, particularly in formal English, but common usage eventually prevails. If enough English speakers insist on something long enough, that will become established English, and individual preferences, house styles, shibboleths, superstitions, conventions, and the rules of grammar themselves will give way before it.
The sensible view is admirably stated by H.L. Mencken in The American Language:
“The error of ... viewers with alarm is in assuming that there is enough magic in pedagogy to teach ‘correct’ English to the plain people. There is, in fact, too little; even the fearsome abracadabra of Teachers College, Columbia, will never suffice for the purpose. The plain people will always make their own language, and the best that grammarians can do is to follow after it, haltingly, and often without much insight. Their lives would be more comfortable if they ceased to repine over it, and instead gave it some hard study. It is very amusing, and not a little instructive.”