When I was young and foolish, I declared that when I grew up I wanted to be the Supreme Dictator of All Things Grammatical. Now that I am older and wiser, I realize my goal was far too limited. I should definitely be the Supreme Dictator of All Things Grammatical and Linguistical.”*
But let’s set aside the linguistical today and just stick with grammatical. Here’s a general rule:
Do not use a period where you should use a comma.
Now, I recognize that there are times when, for artistic effect, it is perfectly reasonable to break this rule. There are times when the greater pause creates greater emphasis. I’m not spitting on you if you don’t always follow this rule, but I will say that there is a limit to how often you can use this technique before it becomes tedious. Burdensome. Just plain ugly.**
Though I joke about being a dictator, I really don’t get annoyed or bothered by a smattering of random mistakes in most published texts.*** Even the very best editors miss things and make mistakes; it is the nature of being human. In small quantities it rarely takes away from the overall product. But when every page contains the same unusual usage in places where it doesn’t contribute to the emotion or pacing or strength of the writing, I must assume that someone just doesn’t know the rule, and that can be distracting. So here’s the specific comma/period rule I want to mention today:
If the phrase after the punctuation expresses a complete thought, use a period. If not, use a comma.
For example, this is wrong:
Wrong: I sat on my bed. Reading a delightful book.
Right: I sat on my bed, reading a delightful book.
Wrong: Then I turned the page. Finding another oddly placed period.
Right: Then I turned the page, finding another oddly placed period.
Now, lest I seem unfair, here’s a place where I think you could reasonably break the rule for effect:
I kept turning pages, discovering more mistakes. Wondering how many there would be. Confused at their frequency.
That’s all, folks. That’s the lesson for today. I know commas are a torment to many a wonderful author. There’s nothing wrong with that. Just make sure that if you are publishing, you have an editor who can fix them up. Plus, now you know this rule at least, so maybe your editor won’t have to charge you as much.
This message brought to you by the Supreme Dictator. Don’t even bother to argue. She’s always right.
* When you’re the supreme dictator, you get to make up words. (Except that sadly I just discovered that the internet thinks this is a word, so I didn't make it up after all. Sigh.)
** See what I did there?
*** And though my friends are sometimes paranoid, I never pay attention to mistakes in personal emails. That’s just crazy.