Are Em Dashes Really a Sign of AI Writing?
In the escalating arms race between AI models like ChatGPT and human beings trying to determine if what they’re reading was machine-generated, there is no easy or surefire way to spot the bot — or is there?
“I — keep — seeing — weird — long — dashes — in — posts,” wrote a LinkedIn user on her page several months ago. “Yes, this is the work of ChatGPT,” she claimed, without proof of the purported em dash craze, let alone the tendency for OpenAI’s bot to spit them out. She didn’t have a problem with anyone using AI to write for them, but rather urged people to edit the em dashes out afterward for readability. “If you’re leaving in these dashes, pause and check,” she advised. In a post around the same time on the ChatGPT subreddit, a user wrote, “I’m becoming increasingly suspicious of emails I’m receiving from a particular colleague who I feel is using AI,” going on to explain: “On[e] thing I notice is that they use ’em dashes’ a lot, for example — like this. Typically, I and everyone else I know use standard hyphens – like this. I didn’t even know there was a shortcut for an em dash until looking this up.”
And in a recent viral Instagram clip from LuxeGen, a lifestyle podcast aimed at a Gen Z audience, one co-host referred to the em dash as “the ChatGPT hyphen.” She said that a fashion company that announced a rebrand with a short statement on social media was facing criticism in the comments from readers who saw two em dashes in the text and immediately assumed they had let ChatGPT write the ad copy. “It’s a longer hyphen, I don’t know if you’ve noticed it,” she added. Like the annoyed LinkedIn user, the hosts agreed that the use of AI per se was not a problem, but that anyone should know to edit whatever the bot produces to “put it in your own words” and “take out the hyphen.”
But there was nothing grammatically incorrect or aesthetically objectionable about how the fashion brand had used the em dashes. Nor is there reason to believe — when even purportedly sophisticated AI filters can falsely identify authentic writing as ChatGPT-generated — that the appearance of any single form of punctuation is a telltale marker of bot text. ChatGPT itself, which if nothing else should know about the history of its own training, will inform you that em dashes “by themselves are not a reliable sign that a text was AI-generated,” and that the popular misconception to the contrary may be a vestige of earlier, less sophisticated models.
“Some early AI-generated content (especially before 2023) used em dashes more frequently than the average human writer,” the bot says. “It was part of mimicking formal or stylized writing.” Now that ChatGPT and similar tools can fine-tune their cadence and tone based on descriptive prompts, it adds, punctuation will vary based on the writing style requested.
On the one hand, the received opinion that the long dash is a product of generative AI that basically didn’t exist in years past is a worrying sign about public literacy: celebrated poets and philosophers from Emily Dickinson to Friedrich Nietzsche have been known to flaunt them in expressive ways, and many people serious about the craft of writing find them useful. Having no basic familiarity with it as a mark on the page is perhaps a measure of one’s limited reading. (That said, famed grammarian and lexicographer Bryan Garner has called it “perhaps the most underused punctuation mark in American writing,” so that could be a factor.)
Yet suspicion of the em dash also speaks to our mounting paranoia over automated communication. (See: the earlier case of the redditor convinced that their co-worker was using AI to write emails.) We are acutely aware that some amount of the media that saturates our waking lives has been spun out of AI models, and we are on the alert for any peculiarity — like, say, extra fingers on an machine-made image of a person — that suggests what we’re seeing is a kind of algorithmic output instead of material that is consciously and intentionally designed by a human being.
When it comes to text, there are a few clear-cut examples of bots flagging themselves, like when attorneys file legal motions that cite nonexistent court cases. The trouble is that merely “polished” writing is now being mistaken for AI content. The models, of course, are trained on a massive volume of professionally composed and edited prose, including books, magazines, academic papers, and so on, and (unlike many people) they follow the rules and conventions of grammar. If a typo or misused word is an indication of a real person at a keyboard, the reasoning seems to go, then the lack of any errors could point to ChatGPT.
This just doesn’t follow, however. We should expect that a major fashion company has copywriters who collaborate on statements shared on the brand’s social media channels, that they agree on the wording of their messaging, that they double-check their spelling, and, yes, even dress up their sentences with a little flair. The em dash has long been a feature of marketing language, helpful in creating rhythm and emphasis. Once you start assuming that any cogently composed piece of text must have come from AI, you are tossing out tons of stuff that took actual labor.
At best, there is only the anecdotal suggestion that that ChatGPT leans on the em dash, with developers in the OpenAI community occasionally griping about how frequently it appears in the bot’s dialogue, sometimes against instructions. In any case, it cannot be a reliable metric of AI reliance for the simple reason that it is a case of the software mimicking human writing patterns. The true signature of a ChatGPT response is more abstract and less definite. It’s the flat quality, the formulaic sentences, the absence of original ideas. Individual writers are made up of idiosyncrasies that a machine doesn’t capture, and they can innovate or adapt in ways that it won’t.
Unfortunately, that leaves us in an ambiguous world where identifying AI-generated text isn’t as easy as noting the appearance of a few horizontal lines. Though as any teacher who grades student essays will probably tell you, it’s possible to get a second sense for ChatGPT without that supposed hack. Over time, the rest of us may develop a better feel for artificial writing — or at least one would hope. At the moment, it looks like em dash enthusiasts will just have to live with the chatbot allegations.
