You want to spot AI-generated text without even reading it? Count the long dashes.
The em dash (—). This little punctuation mark was living its best life in English typography for centuries. Then AI decided to make it its favorite toy. Every sentence. Every response. No exceptions.
Open ChatGPT. Ask it anything. An email, a LinkedIn post, a cover letter, a pasta recipe. You'll get hit with em dashes every other line. It's systematic, it's mechanical, and it's annoying as hell.
And here's what pisses me off: nobody actually writes like that. Have you ever seen a coworker drop an em dash in a Slack message? No. Because normal people use commas, periods, parentheses. Normal stuff.
So why do AIs do this?
Because they've been force-fed millions of "well-written" texts. Blog posts, Medium articles, technical documentation. And in that kind of content, the em dash is the universal sign of "I know how to write." The model got the message loud and clear: long dash = quality. So it throws them around like an intern at a content agency who just read their first copywriting guide.
On top of that, the em dash is the Swiss Army knife of punctuation. It replaces commas, colons, parentheses. When the model hesitates between three punctuation marks, the em dash works everywhere. It's the default choice. The path of least statistical resistance.
And it gets worse
During training, humans rate the AI's responses. The ones that "sound good" get rewarded. Em dashes sound good. So they get rewarded. So they come back. Again and again and again. The model reinforces its own tic. It's a typographical vicious cycle.
The result: the em dash has become an involuntary watermark. A "generated by AI" stamp that the model slaps on its own face. You don't even need an AI detector. Just count the long dashes and you've got your answer.
Just the tip of the iceberg
And that's not all. The "it's worth noting", the "let's dive in", the bullet points in every single response, the "moreover" at the start of every paragraph... AI has a writing style. You can recognize it from a mile away. And if your content sounds exactly the same, you've got a real credibility problem.
What's the AI writing tic that annoys you the most?
Top comments (8)
I have seen humaniser skills and one of the rules is don't overuse em dash. So people are just not using the skill.
The worst AI writing tic is that is too often non-assertive. There is a line where being assertive is good.
Like people waiting endlessly to merge into traffic. Especially at a crossroad that can result into road rage.
Yes indeed ! It’s another point but you spoil my content for tomorrow 😂 Anyway, the em dashes is my first clue to see if the content written worth my time or not
I understand your reluctance. On the other hand someone that doesn't has English as their native language or as a lesser known language AI corrections can be a tool to make them more confident to publish their content.
At the moment I'm not that bothered anymore about the em dashes. I do think it is a cool English sentence construct like the Oxford comma. Of course the over use by AI made it ridiculous.
Also all the LLM's have the same overuse, I wonder who was the person that decided it should be a thing to bring back. Who is the em dash Satoshi Nakamoto?
For what it's worth I love emdashes and have used them for years 😭
Really, never saw one of them before 2023 ahah, there's a lot more than em dashes that betray AI copywritting, But if your prime minister two em dashes per sentence, that mean that he just used chatGPT 🤣
This is the kind of meta-observation I live for. 😂
Now I'm going through my old posts like a detective looking for em dash crimes. And yep they're everywhere in the AI-assisted sections.
I've noticed Claude loves delve and tapestry too. It's wild how these tiny patterns become watermarks.
Also love that you called out the irony your title has an em dash and I'm guessing that was 100% intentional 😄
Great read, Valentin. Your "Day I Let AI Write the Code" post actually inspired my recent article. So thanks for that! 🙌
Thanks Harsh! Yes — the — title — em — dash — was — 100% — intentional 😄
“Delve” and “tapestry” are definitely on the list. I might do a follow-up ranking the worst offenders. The em dash is just the most visible one because it’s a punctuation mark, not a word. You can’t hide it.
Glad the previous post sparked something for you, that’s the best. Looking forward 🔥
The first "—" is a joke in case you didn't get it 🤣