Brando Miranda — May 2026 · ~1 min read

TL;DR. The em dash is only an AI fingerprint if it was not already part of the writer’s fingerprint. Some of us were dash people long before ChatGPT made punctuation suspicious. I got mine from William Zinsser’s On Writing Well, where the dash is treated as a normal, useful piece of nonfiction craft. The mark is not the giveaway. The baseline is.

There is a small, ambient annoyance I have been carrying for the past year, and I want to put it down.

People keep telling me that my writing “sounds like AI” because I use em dashes. The accusation is usually delivered as a compliment-shaped jab: “great post, but you should maybe dial back the em dashes, it makes it look generated.” I understand where the suspicion comes from. Long-form models do over-use the em dash, and pattern-matching on punctuation is a cheap heuristic for spotting low-effort text.

The problem is not that the heuristic is always false. The problem is that it ignores the author’s baseline. If someone never used em dashes, then suddenly starts writing every paragraph like a LinkedIn ghostwriter with a punctuation sponsorship, fine, raise an eyebrow. But if someone was already using them before the current AI panic, the dash is not an AI fingerprint. It is just a fingerprint.

In other words: the em dash is only an AI fingerprint if you did not already use it.

I bought William Zinsser’s On Writing Well years before GPT-3, before ChatGPT, before “ChatGPT-style writing” was a phrase anyone said out loud. There is a chapter called “Bits & Pieces,” and inside it Zinsser gives the dash full citizenship in good English. The em dash did not arrive with AI. Some of us were using it back when the hot productivity stack was underlining a paperback and feeling profound about it.

Zinsser’s first example is simple: “We decided to keep going—it was only 100 miles more and we could get there in time for dinner.” The dash is not decoration there. It turns the sentence forward and gives the reason. His other use is the parenthetical aside: a thought inside a thought, without stopping the sentence cold.

That is why I use it. Not because it is a vibe, not because it performs intelligence, and not because it carries some secret modern signal. I use it because sometimes the sentence wants a turn, and the dash is the cleanest turn available.

Calling that an AI fingerprint is like calling clean indentation a Copilot fingerprint. The tool was a tool before the panic started. The flattering version is that cool people like me were simply early.

A practical request: when you see writing you suspect of being generated, do not start with one punctuation mark in isolation. Compare it to the author’s prior writing. Then look at the thinking. Is there a claim in the post that the author committed to? Is there a counter-argument they actually wrestled with? Is there a sentence that could only have been written by someone with skin in the game? Those are the fingerprints worth checking.

In the meantime, I am keeping my em dashes. Zinsser got there first, I got there before the panic, and the dash remains undefeated ;)

If you’d like to cite this post:

@misc{miranda2026emdash,
  author = {Miranda, Brando},
  title  = {The Em Dash Is Only an AI Fingerprint If You Didn't Already Use It ;)},
  year   = {2026},
  month  = {May},
  howpublished = {\url{https://brando90.github.io/brandomiranda/2026/05/04/em-dash-not-an-ai-fingerprint.html}},
  note   = {Blog post}
}