National Punctuation Day: Learn the Rules Before AI Forgets Them For You

TL;DR: National Punctuation Day is September 24, founded in 2004 by Jeff Rubin to fight sloppy punctuation. I did not know it existed until now, but I am all in, because punctuation is having a strange moment. AI is quietly funneling everyone toward the same mediocre writing, and it has even made the em dash a suspect. Here is the history, my honest take, and the simple habit that will make your punctuation better than any AI’s.

A Real Holiday for the Comma

National Punctuation Day exists because one former newspaper reporter got tired of misplaced commas. “Let’s eat Grandma” versus “Let’s eat, Grandma.” One of those is dinner. The other is a crime.
Share on X

National Punctuation Day is September 24, and I will be honest, I did not know it existed until I sat down to write this. Now that I do, I am glad it is there. It was founded in 2004 by Jeff Rubin, a former newspaper reporter who got so tired of seeing punctuation butchered in print that he made a holiday out of it. He moved it to September 24 to line up with the school year and to honor the jersey number of his baseball hero, Willie Mays.

The point of the day is simple and correct. Punctuation is not decoration and it is not optional. It carries meaning. The classic example says it all. “Let’s eat Grandma” and “Let’s eat, Grandma” are two very different sentences, and the only difference is one comma. One is dinner with Grandma. The other is cannibalism. That little mark is doing real work, and so are all the others. Punctuation is how written language tells you where to pause, what connects to what, and who exactly is getting eaten.

My Real Pet Peeve: AI Is Flattening Everyone’s Writing

AI is quietly funneling everyone toward one standard of writing, and that standard is mediocre. A lot of it was trained on Reddit and Wikipedia. The result reads exactly like that.
Share on X

Here is what actually worries me about writing right now, and it is bigger than commas. Artificial intelligence is funneling everybody toward a single standard of writing, and that standard is not good. It is mediocre at best.

I keep seeing people accept AI-written text as if it is good writing, and most of it simply is not. It ranges from mediocre to bad. AI has certain patterns it falls into, recognizable tics and rhythms, and those patterns are not good writing. That makes sense when you remember where a lot of AI learned to write. Much of the training came from places like Reddit and Wikipedia. Now, a Reddit post can be brilliant, funny, sharp, even moving. But nobody is claiming Reddit is punctuation perfect or a model of polished prose. Train a machine on oceans of average writing and it produces average writing, confidently, forever.

The strangest casualty of all this is the em dash. The em dash is now treated as a sign that AI wrote something, so people have started avoiding it like it is contraband. This is silly. The em dash is a completely valid piece of grammar that has been used by great writers for centuries, and it should be used whenever it serves the sentence. Banning a legitimate mark because a chatbot likes it is letting the machine dictate your style. I happen to avoid em dashes in my own published work, but that is a deliberate house-style choice I made, not a confession that the mark is wrong. There is a real difference between choosing not to use something and being scared to use it because of what people might assume. Make your punctuation choices on purpose, not out of fear.

The Habit That Beats the Machine

Do not guess at a comma. Look it up. Every time you wonder how punctuation works, open the Chicago Manual of Style and find out. Do that enough and you will never need to wonder again.
Share on X

So how do you write better than the average machine? You learn how your language actually works. That is the whole secret, and it is not complicated.

Understand how punctuation works. Understand how your language is built. And when you are not sure about something, do not guess. This is the habit that changes everything. Most people, when they hit a comma they are unsure about, just think to themselves, “I’ll use a comma this way,” and move on, inventing a rule on the spot. Do not do that. Instead, go look it up. Open the Chicago Manual of Style, or whatever style guide you are writing against, and find the actual rule for that comma. Then use it correctly.

The Chicago Manual of Style is the standard for most book and general publishing in the United States, and you do not have to memorize it. At least skim the important sections so you know what is in there, then look things up as you need them. Every time you look something up instead of guessing, you learn it a little more permanently. Do that enough times and the rules stop being mysteries. You start to actually know your craft at the level of the comma, which is more than most writers and more than any chatbot trained on Reddit will ever truly understand.

Two Books That Make Punctuation Painless

If a full style manual sounds dry, start with two books I keep in my own library, both of which make this stuff genuinely enjoyable.

The first is Eats, Shoots & Leaves by Lynne Truss. The title comes from a joke about a panda and a badly punctuated wildlife manual, and the whole book is like that, funny and sharp while it teaches you real rules. It is a bestseller for good reason. It is not hard, and it will make you care about punctuation in spite of yourself.

The second is Whose Grammar Book Is This Anyway? by Edward Good. It is another approachable, friendly guide to the rules of English, the kind of book that explains grammar and punctuation without making you feel like you are back in a classroom you hated. Both of these are in my library, and both are worth yours. Read them, keep a style guide nearby, and look things up. That is how you punctuate like a professional instead of like a prediction engine.

What This Means for Writers

The deeper lesson of Punctuation Day, in the age of AI, is about ownership of your craft.

Punctuation is one of the clearest places where a real writer separates from a machine and from a lazy one. Anyone can let autocorrect or an AI tool make the calls. A writer knows why the comma goes there, chooses the em dash on purpose or leaves it out on purpose, and controls the rhythm of a sentence deliberately. That control is not pedantry. It is craft. It is the difference between writing that sounds like a person who knows what they are doing and writing that sounds like everything else being churned out right now.

So on September 24, do something small and powerful. Find one punctuation rule you have always just guessed at, and look it up for real. Learn it. Then write a sentence using it correctly, on purpose, like someone who owns their craft. That is worth more than a thousand words of confident, mediocre, machine-smoothed prose.

National Punctuation Day FAQ

When is National Punctuation Day?
September 24 every year. It was founded in 2004 by former newspaper reporter Jeff Rubin to promote correct punctuation, and moved to September 24 to align with the school year.
Are em dashes a sign of AI writing?
No. The em dash is a valid, long-established piece of punctuation used by great writers for centuries. It has recently been treated as an AI tell, but avoiding a legitimate mark out of fear is letting machines dictate your style. Use it, or skip it, as a deliberate choice rather than a reaction.
What is the best way to learn punctuation?
Stop guessing and start looking things up. When you are unsure about a comma or any mark, open the Chicago Manual of Style or whatever style guide you write against and find the actual rule. Each time you look something up instead of inventing a rule, you learn it more permanently.
What are good books for learning punctuation?
Two friendly, enjoyable ones are Eats, Shoots & Leaves by Lynne Truss, a witty bestseller about why punctuation matters, and Whose Grammar Book Is This Anyway? by Edward Good, an approachable guide to the rules of English. Pair either with a style manual like Chicago.
Why does punctuation still matter in the age of AI?
Because AI tends to produce mediocre, pattern-driven writing, much of it trained on average text from sources like Reddit and Wikipedia. A writer who genuinely understands punctuation controls rhythm and meaning deliberately, which separates real craft from machine-smoothed, interchangeable prose.

📝 Disclaimer

The views and opinions expressed in this blog post are solely those of Richard Lowe and are based on personal experience and research. This content is for informational purposes only and should not be construed as professional legal, financial, accounting, or business advice. Always consult with qualified professionals before making important business or legal decisions. Richard Lowe is not a lawyer, accountant, or licensed professional advisor, and this content does not establish any professional relationship.

Receive the latest news

Before you go, grab four free guides

On writing, publishing, and selling your book. Free, straight to your inbox.