- Make sure you understand what the general Aesop of your story is. If you don't know what you're writing about, it's just flat out not going to work.
- Examine your heroes' actions in detail. With everything they do, repeat your Aesop and ask yourself - do they do as you tell them, or do they do the exact opposite?
- Also examine your villains' actions in detail. If they are actually following the aesop, then ask yourself how you treat them in comparison to the heroes. Do you treat them as an Anti-Villain who the heroes admit makes sense, or do you treat them as a Complete Monster who is wrong about everything? The first example can add a layer of moral ambiguity to the story, while the second example breaks the aesop since villain or not, they are following the aesop, and makes it seem like it's only okay when the heroes follow the aesop.
- If the aesop is about a real world issue, do the differences in setting break the aesop? For example, a fantasy story using Fantastic Racism as a metaphor for real world discrimination is easy to break because the people practicing Fantastic Racism in that setting might actually be justified in their fear of a specific race. If they have powers that are potentially deadly or have a tendency to enslave or kill other races, then the people fearful of them have plenty of reasons to fear them. Another factor to consider with this type of aesop is if you try to act like Humans Are the Real Monsters. If you portray everyone in your fantasy race as victims of racism and have all the bigots be humans, that makes it seem less like racism is bad in general and more like racism is good or bad depending on which group is discriminated against. In this case, despite trying to say racism is bad, you're fine with painting humans in a negative light just so your fantasy race can have the moral high-ground.
So You Want To / Avoid Breaking Your Aesops
So, say you're doing a work and want to teach your readers something. Perhaps you believe that Science Is Bad. However, you need to avoid one dreaded pitfall - a Broken Aesop, when the heroes of your story break the rule you're trying to teach your readers. How to avoid it?