Walking the streets of New York , nothing cheers me up like signs written under the impression that quotation marks convey emphasis. One of my favorites is a cleaners that advertises its “FREE PICK UP AND DELIVERY” as if there’s something hypothetical about the service.

Or, another shop has “DROP OFF YOUR LAUNDRY ON YOUR WAY TO WORK, ‘PICK IT UP ON YOUR WAY BACK HOME.'” Then there’s one I used to pass every day, a candy store telling us that “WHEN IT COME TO NUTS, CHOCOLATES AND CANDIES, WE ARE THE BEST.” Call it the new boldface.

The grammar of that last one reflects that most of these shops are run by immigrants, who often have limited knowledge of English, especially the nuances of English as it is written. Native-born Americans are hardly strangers to the new boldface, either, in which case it seems to be related to educational level.

It is an understandable mistake. Quotations set off something, and it’s a short step from setting something off to emphasizing it. For someone who has never read much, at least in English, it’s natural to suppose that quotation marks are highlighters, since in a way, they are.

Thus I can wrap my head around why someone would advertise their restaurant as serving “FINE FOOD.” There are now legions of people who have an alternate conception of what quotation marks are used for, using it with considerable consistency — notice people do not use them in place of hyphens or semicolons.

However, fans of books like “Eats, Shoots and Leaves” have nothing to fear. There is no reason to suppose that America is on its way to no one knowing the difference between quotation marks and emphasis.

Written language is more resistant to change than spoken language. At all times there are all kinds of things going on in spoken language and in less formal written language which leave standard written English sailing serenely along untouched. Even standard English is used less formally today than it was back in the old days, but there are still limits. Notice how many people say That’s a whole nother issue , and how we rarely if ever encounter “whole nother” in print, except if a person is quoted. There is also no significant relationship between how people write e-mails and the prose of the Wall Street Journal or even Tiger Beat.

Which means that the new boldface will just hang around as an underground alternative punctuation. New generations of immigrants will pick it up from older ones’ signs, and there will always be native-born Americans who use it this way. The standard written language, however, will not take it up.

Of course to many, the new boldface is simply “wrong.” However, as a linguist I have a deep-seated skepticism toward much of what we are taught and think it is so conclusively “wrong” in the way we speak and write.

I value graceful expression as much as anyone. What gets ticklish for me are claims that it is, for example, “wrong” to use impact as a verb. Quite simply, the verbs view, silence, worship, copy, and outlaw all began as nouns. No one has a problem with them.

Thus wearing my linguist hat, I am inclined to treat the new boldface as a variant usage of punctuation which, since it is used consistently by users, cannot on any logical grounds be rejected as “wrong.”

After all, just as nouns are always becoming verbs in English, even the uses of punctuation change, and I don’t mean across vast expanses of time such as that which separates us from Shakespeare. A hundred years ago in America it was considered good style on signs to put a period after nouns used alone. Across the street from me, the facing on a house was removed and revealed an antique sign that read PATTERN MAKERS. although “pattern makers” is not a sentence. You commonly see periods used this way in photos of the era.

So apparently the usage of quotation marks is different now than back then just as with periods. This is my arid intellectual take on it. More viscerally, however, I have come to accept the new boldface just as much for how much it makes me laugh after a long day. My life would be poorer if a laundromat in my neighborhood did not display a bracingly skeptical sense of its own existence with its sign “CAROLINA’S.”

Indeed, the new boldface can be a vehicle of considerable philosophical nuance. I am still trying to figure out what one of my favorite signs, regretfully no longer extant, meant by advertising its salad bar with CREATE “A” SALAD.

Mr. McWhorter is a senior fellow at the Manhattan Institute.