From Cecelia Watson's fine book "Semicolon: The Past, Present, and Future of a Misunderstood Mark", the following quote is not only a piercing diss of DFW's "logic" on why one "must use" Standard written English, but a pointer to why one must read the book from where this is quoted:

The finest deployment of semicolons I’ve ever come across, in fact, is in Martin Luther King, Jr.’s “Letter from Birmingham Jail,” which King wrote longhand in the margins of a newspaper while imprisoned in Alabama for civil disobedience. The letter defends King’s agitation for civil rights against fellow clergymen who felt he should show more patience. The passage from the letter that contains the remarkable semicolons is a long one, and I suggest reading it out loud to really feel their effects.

This is the piece by Martin Luther King:

Perhaps it is easy for those who have never felt the stinging darts of segregation to say, “Wait.” But when you have seen vicious mobs lynch your mothers and fathers at will and drown your sisters and brothers at whim; when you have seen hate filled policemen curse, kick and even kill your black brothers and sisters; when you see the vast majority of your twenty million Negro brothers smothering in an airtight cage of poverty in the midst of an affluent society; when you suddenly find your tongue twisted and your speech stammering as you seek to explain to your six year old daughter why she can’t go to the public amusement park that has just been advertised on television, and see tears welling up in her eyes when she is told that Funtown is closed to colored children, and see ominous clouds of inferiority beginning to form in her little mental sky, and see her beginning to distort her personality by developing an unconscious bitterness toward white people; when you have to concoct an answer for a five year old son who is asking: “Daddy, why do white people treat colored people so mean?”; when you take a cross country drive and find it necessary to sleep night after night in the uncomfortable corners of your automobile because no motel will accept you; when you are humiliated day in and day out by nagging signs reading “white” and “colored”; when your first name becomes “nigger,” your middle name becomes “boy” (however old you are) and your last name becomes “John,” and your wife and mother are never given the respected title “Mrs.”; when you are harried by day and haunted by night by the fact that you are a Negro, living constantly at tiptoe stance, never quite knowing what to expect next, and are plagued with inner fears and outer resentments; when you are forever fighting a degenerating sense of “nobodiness”—then you will understand why we find it difficult to wait.

Cecelia Watson, continued:

I’m hardly the first person to home in on the conventionality of King’s register. It gets a mention in a speech that the novelist, essayist, and English teacher David Foster Wallace liked to give to black students whose writing he perceived to be, unlike King’s, “nonstandard.” Wallace gave this speech one-on-one to students he believed would benefit from it. It’s long, but here’s a taster...

David Foster Wallace:

I don’t know whether anybody’s told you this or not, but when you’re in a college English class you’re basically studying a foreign dialect. This dialect is called Standard Written English. . . . In this country, SWE is perceived as the dialect of education and intelligence and power and prestige, and anybody of any race, ethnicity, religion, or gender who wants to succeed in American culture has got to be able to use SWE.

This is just How It Is. You can be glad about it or sad about it or deeply pissed off. You can believe it’s racist and unfair and decide right here and now to spend every waking minute of your adult life arguing against it, and maybe you should, but I’ll tell you something—if you ever want those arguments to get listened to and taken seriously, you’re going to have to communicate them in SWE, because SWE is the dialect our nation uses to talk to itself.

African-Americans who’ve become successful and important in US culture know this; that’s why King’s and X’s and Jackson’s speeches are in SWE . . . and why black judges and politicians and journalists and doctors and teachers communicate professionally in SWE. . . . And [STUDENT’S NAME], you’re going to learn to use it too, because I am going to make you.

Cecelia Watson, continued:

This speech, Wallace claims, is in the service of being honest and realistic about the way that language is wrapped up in politics and power. Students should be pressed into choosing to learn what Wallace calls SWE—Standard Written English, or Standard White English, as he acknowledges it might as well be called. The reason students should be required to learn SWE is that they will be at an extreme disadvantage in the world if they do not do so. This is how the world is whether you like it or not, Wallace says, ostensibly congratulating himself on his brave truth telling.

Apparently a few students who were subjected to this speech were offended by it, and one lodged an official complaint with the university. I have some complaints about it, too. Did Wallace pull all his white students into his office for an in-camera chat about how it is that they might be upholding elitist power structures by speaking and writing SWE? Did Wallace call out his colleagues in the academy for failing to find ways to make room for ideas expressed by people who might not know—or might simply choose not to use—the secret-handshake grammar of the powerful? Did he make participation in SWE a choice as fraught with moral and political implications as he made nonparticipation in that dialect? No, the onus is on the black student to choose, not on Wallace or anyone else to use his power and privilege to help remake the world.

Later in the essay, he tells the reader that what must have been offensive to the student who complained about his speech was only that he, a privileged white male, was the one making it. Because of his identity, he says, the student just wasn’t able to see the “logic” of his speech. Nice try, DFW, but what logic? So—your argument is “We must use one form of speech, Standard Written English, because that’s the form of speech we always use.” I’m not persuaded that “we are doing this already” is sufficient to justify a claim that “we ought to continue to do this” or “we must continue to do this.” Logic is about uncovering and examining assumptions, not perpetuating them. Maybe there is an intelligent, logical argument to be made for choosing SWE as a shared scholarly and professional dialect—but Wallace didn’t bother making it.

What is most infuriating about reading Wallace—more infuriating even than his factual errors and logical hiccups, of which there are many in the “American Usage” essay*—is that it seems he was equipped to understand, for instance, that language is part of our self-presentation, crucial to our construction and conception of ourselves. He understood better than most people that language, and the choices we make surrounding it, is political, always. Yet in his “pep-talk” to black students, he didn’t see it as his job to create a world that would be more open to more possible selves than ones like his own. It’s a good thing to make students (and even people who’ve left their student days far behind) aware that there are context-specific costs and benefits in the choice of one English dialect over another. The problem is that Wallace exempts himself (and everyone who already speaks and writes like he does) from responsibility for his own choice, by pretending it isn’t a choice at all.

It’s an attitude in keeping with Wallace’s self-proclaimed snobbery. He was profoundly a snob—or as he called it, a SNOOT, an acronym Wallace’s family used for “somebody who knows what dysphemism means and doesn’t mind letting you know it.” A dysphemism is a derogatory term—like snoot, for instance—and you shouldn’t feel bad if you didn’t know that, nor should you feel exceptionally clever if you did and you got the joke. Each of Wallace’s sentences is a stunt of some kind, every clause an Odyssean convolution. For him, being a SNOOT was something to brag about, and it’s crucial to his literary style. When I look back on my own snob days, I feel it’s something to be embarrassed about. Where Wallace sees moral high ground lush with the fruits of knowledge, I see a desolate valley, in which the pleasures of speaking “properly” and following rules have choked out the very basic ethical principle of giving a shit about what other people have to say.

Wallace cared a lot about language and punctuation, and I have no problem with that. I love that at his book readings, he read his punctuation aloud along with the words, because he put those punctuation marks in his writing for a reason. His enthusiasm for punctuation and for language more broadly is not the problem, and I don’t doubt that he took his role as a teacher of young people seriously. What is problematic to me is the direction in which he chose to channel those interests and concerns: he narrowed the conversation about the politics of language rather than expanding it, by making it one-sided and doing what everyone always does—obligating people who aren’t participating in the status quo to step it up rather than asking the people enforcing the status quo to think about, and justify, their own standards and values.

So what happens now, if you’re ready to entertain the notion that having plum-picking contests and SNOOTing around isn’t the most admirable way to behave? What’s left, if we aren’t supposed to show our respect and love for language by respecting and loving rules?

It’ll be clear to you by now that I disagree with the rule mongering of the David Foster Wallace types, and the semicolon hatred of Professor Paul Robinson, the guy who feels “morally compromised” when his pinkie finger plunks the semicolon key. The history of punctuation shows that rules can’t be taken for granted as necessary elements of language. For a start, when we consider rules, we have to ask: whose rules? Exactly which collection of rules are we supposed to rely upon and remember, when the fortunes of rule systems have depended on their contradicting one another? For over two centuries, grammar books have preached the gospel of rules, and now, when I talk to friends, students, and colleagues about grammar, they lower their voices confidentially to confess sins: I just don’t ever use the semicolon, because I’m afraid I’ll do it wrong. I sometimes want to use two colons in one sentence, but I’m not allowed. I am very confused about the Oxford comma. Occasionally I’ve been pulled aside after a talk on the semicolon to be told a story about a dogmatic elementary school English teacher still perched on the now-adult student’s shoulder, looking down, judging, even after decades. At times I’ve felt less like a punctuation theorist than like a punctuation therapist.

For a taste of some of the problems with Wallace’s essay, see the Language Hat blog’s entry “David Foster Wallace Demolished,” http://languagehat.com/david-foster-wallace-demolished/, accessed August 5, 2018. In addition to the mostly sentence-level problems that Language Hat highlights, there are glaring argument-level flaws. Those flaws would require a longish essay to elucidate properly, and this book is not the place. The essay is useful here as an example of a very common and very misguided expectation that users of “standard” English are exempt from justifying that choice.

http://languagehat.com/david-foster-wallace-demolished/