Note on 17th March 2026

2026-03-17T13:00:00+00:00

Em-dashes have become a telltale sign of AI-generated text, which has created some funny side effects.

I now frequently see correct and incorrect usage of hyphens and dashes mixed in the same piece of text. This happens when someone revises a piece of AI-generated text but doesn't understand the difference between hyphens, en-dashes, and em-dashes.

It's also pretty obvious that some people have started find-replacing all em-dashes with single hyphens (-) or double hyphens (--) to hide that they used AI. Which, of course, is its own tell.

But this still doesn't hide the most obvious giveaway, which isn't the em-dash itself. LLMs almost always put spaces around em-dashes: word — word instead of word—word. My guess is that models are heavily trained on news data, where the AP style guide, most commonly used in journalism, recommends spaces around em-dashes. Books and most professional writing use them without spaces.

So if you're taking your writing seriously, there's no way around learning how to use hyphens, en-dashes, and em-dashes correctly. I wrote a short post explaining the differences on my blog: Hyphens and Dashes

View the original LinkedIn post

Tags: linkedin, ai, writing

Hyphens and Dashes

2026-03-16T20:57:56.802522+00:00

With AI tools becoming widely adopted, em-dashes have become a telltale sign of AI-generated content. Claude and ChatGPT seem to love them, which is unfortunate, because it's now made everyone suspicious of a perfectly good punctuation mark. But this doesn't change the fact that most people (non-native and native English speakers alike) never learned or understood the difference between hyphens (-), en-dashes (–), and em-dashes (—) in the first place. I now frequently see correct usage (AI-generated) and incorrect usage mixed in the same document, which happens when people do not understand the difference and revise a piece of AI-generated text.

The differences may seem subtle at first, but incorrect usage is unprofessional and can change the meaning of a sentence. Once you understand the distinctions, it's hard to unsee when people use them incorrectly. There is also a trust dimension to this. As a reader, if someone didn't put in the effort to write correctly, how can I trust that they put in the necessary effort into the thinking behind what they wrote?

I first learned about these distinctions during my PhD when I started writing scientific papers. David Norris, my supervisor and a great writer, had a habit of returning our manuscripts with red ink covering almost every page but rarely any explanations. You were expected to figure out what was wrong. Freddy Rabouw, then a postdoc in our group, took the feedback he received seriously, dug into the rules, and created a short presentation for the whole lab. The rules are simple once you learn them, but nobody teaches them.

When to Use Which

The best single resource I know is Typography for Lawyers. Here's my condensed version with tech-world examples.

Hyphens (-) connect compound words and phrasal adjectives: AI-generated text, real-time processing, third-party API. The logic is that when two or more words work together to modify a noun, you hyphenate them before the noun. "An AI-generated response" but "the response was AI generated." One exception: don't hyphenate when an adverb ending in -ly does the work. It's highly scalable infrastructure, not highly-scalable infrastructure.

Missing hyphens can create genuine ambiguity. Consider "small business software": is it software for small businesses, or small software for businesses? With a hyphen, small-business software is clearly software for small businesses. Or "new user onboarding": is the onboarding new, or are the users new? New-user onboarding removes this ambiguity. In AI contexts, "few shot prompts" could mean a small number of shot prompts, whatever those are; few-shot prompts makes clear we're talking about prompts for few-shot learning.

En-dashes (–) are slightly wider and are used in two cases. First, they mark ranges: 2020–2023, pages 50–75, chapters 3–7. (But if you start with "from," use "to" instead: from 2020 to 2023, not from 2020–2023.) Second, they denote connections or contrasts: product–market fit, the London–New York route, key–value cache.

Em-dashes (—) create a break when commas are too weak, but colons or semicolons feel too heavy. Used well, they add rhythm and emphasis, but overused, they make text feel breathless, repetitive, and AI-generated (yes, this is a compound modifier too!).

A Bonus Tip for the AI Age

Maybe incorrect usage of hyphens is now a charming sign that someone actually wrote it themselves. Some people have caught on and started find-replacing all em-dashes with single hyphens (-) or double hyphens (--) to hide that they used AI, which is its own tell. But this still doesn't hide the most obvious giveaway, which isn't the em-dash itself. LLMs almost always put spaces around em-dashes: "word — word" instead of "word—word."

My guess is the models are overtrained on news data, and the AP style guide, which is most commonly used in journalism, recommends spaces around the em-dash. Books and most professional writing use them without spaces.

I'd been avoiding em-dashes entirely for the past year because of this association—noticing the space pattern finally lets me reclaim them for my own writing.

Tags: writing

Quoting Bill Gurley

2026-02-27T07:39:07.457006+00:00

I think for anybody in any field, if they write about the edge of what's happening in their field, [...] it really hones your thinking, because when you write something down and you do it all the time, there's this inner desire to not be intellectually inconsistent and so you hold yourself actually to understanding things. Going back to that word nuance, you really get into the nuance because you really want it to hold together once you put something down on paper and there are plenty of people outside of ourselves that have studied this writ large, but it's very well understood that writing is a great way to understand things to take it to a higher level.

— Bill Gurley, Stratechery interview about Gurley's book Runnin' Down a Dream

Tags: stratechery, blogging, writing

Felipe Antolinez's Weblog: writing

Note on 17th March 2026

Hyphens and Dashes

When to Use Which

A Bonus Tip for the AI Age

Quoting Bill Gurley