I don't write non-fiction. (One day I might, I have some ideas.) But this topic is about credibility in fiction.
Some people out there are probably saying "What? It's fiction. It doesn't have to be real, right?" True, it doesn't have to be an actual course of events. But you're still asking a reader to believe it. Why? Because if a reader is gonna escape into your book, they need to feel like they're not being lied to or they'll leave.
And then my favorite response to this is "I write fantasy. It doesn't have to be real." Of course not. All fiction is supposed to be--well--fiction, no matter the genre. But what you need is to have a world presented in such a way that the reader isn't going to say "Even for this world, that's impossible."
Let me give an example of how this would work. I'm going to go at the easy scapegoat: Twilight. Now, I've never read Twilight. But, I've seen the movie. By no means would I claim to be an expert on the story. I just know enough of it. So let's say Bella walked out of school and all of a sudden a dragon appeared. And Jacob and Edward had to team up to take the scary beast out.
Now as cool as that would be, it just isn't plausible. The world Stephenie created isn't a world with dragons in it. It's a world with humanoid mystical beings. There aren't elves and dwarfs running around. Bella and Edward didn't leave their wedding on their brand new USS Redwood space shuttle.
This is a pretty drastic example, but the point is there. Sometimes, we may do something that pulls our reader out of believing in our story. It could be something as subtle as missing an eye-color change. Perhaps it's a day of the week. FYI, I've read 2 published books where the author wrote one day down and then wrote another day down shortly thereafter as if referring to the first date stated. Inconsistency is a pill and I'll catch it most of the time. Another one I read about a character's ancestor. This ancestor went from great-grandfather to great-great-great-grandfather to great-great-grandfather.
If you can't keep your "facts" straight, you can't keep my attention.
So there we have "mismatched world" and "consistent data". Other ideas? Verbiage. If your character doesn't swear, then don't suddenly make him swearing up a storm if nothing set him off. Don't go back and forth between 19th century Queen's English and 21st century Ebonics. I won't like you. If you mesh them? You better do it right or your story's going to be put with my 3yo's stinky diapers.
Okay, that's enough ranting. (FYI, I suck at verbiage, so I'm reminding myself where my stories may end up.)
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