How to Write a Chiasmus
The structure of a chiasmus is pretty simple, so they aren’t difficult to craft. All you have to do is make up the first half of the sentence, and then flip a couple of words around for the second half. However, a good chiasmus works because it encapsulates a genuine insight about the world, and those are not easy to come by!
The best advice is just to observe as many examples of chiasmus as possible. Read broadly, and see what kinds of ideas are best expressed through a chiasmus. By absorbing lots of examples of this structure, you’ll train your brain to think creatively about how you can flip ideas around to generate your own chiasmic structures.
One other note of caution: when the concepts are unclear or unfamiliar, a chiasmus can actually be a pretty confusing sentence structure! (See the example from Karl Marx in Section 7.) After all, the chiasmus expresses two very separate ideas in rapid succession, which means the reader has very little time to take it all in. So if you’re using a chiasmus to express a complicated idea, take some time to elaborate and explain yourself afterwards. Don’t just assume that the reader knows what you mean by your chiasmus!
When to Use Chiasmus
Chiasmus is equally appropriate in all rhetorical situations and all types of writing – formal essays, fiction, creative nonfiction, poetry, etc. In addition, it appeals to all types of audiences, including children! However, it is a sophisticated rhetorical device, and probably wouldn’t appear in the dialogue of an uneducated or bumbling character. In other words, the only time when you would need to avoid chiasmus is if you’re trying to make a character sound dumb!