So, what do you do when you have a character who wants nothing to do with what’s going on in your story?

Well, you have to persuade them to change their minds. And to do that, you have to understand how to show believable decisions in fiction.

Step One is to come to grips with the fact that reality is frequently unbelievable. Many things that you do in your day to day life are going to look flat out unbelievable if they’re used in fiction. A case in point, every day you make decisions, both significant and insignificant, with little or no thought, deliberation or outside input. You can eat toast with peanut butter every morning for the rest of your life for no reason more significant than it’s a fast and tasty morning meal.

However, the Law of Conservation of Detail says that everything you show your character doing must be important to them. If your character eats toast and peanut butter every morning, it had better be because they love peanut butter. In fact, whenever they eat it there had better be something peanut butter based around, and they should vocally proclaim the superiority of peanut butter to anyone around. (A simple enough task for anyone who’s ever tasted it.)

Second, you need to remember the Law of Cause and Effect (sadly without a TV Tropes page) – everything must happen for a reason, and your reader has to be given a chance to see what the reasons are. That takes a lot of different forms, but for the purposes of character building, it means that whenever your character makes a decision the reader has to know why.

You probably make a dozen decisions every day without any kind of prompting or ever stopping to reflect on it or explain yourself to anyone, so it can be easy to slip into the habit of writing characters who just do something on the spur of the moment. But in order for your characters to be understandable and believable, you need to do something that, on the face of it, may seem unbelievable: You’ll need to show what leads up to every decision your character makes. (And remember, Conservation of Detail says every decision you show them making had better be important.)

That can take several different forms. Characters can talk over decisions before they make them. That’s probably most suited for major decisions that are going to impact a large portion of your cast. On the other hand, a character can take some simple action that illustrates the reason for his decision. For example, if the protagonist decides to take his group of friends to a specific restaurant for dinner, he glance around for the favorite uncle who manages the eatery.

There are other, more subtle ways of showing how the character’s decisions are influenced. Other characters might say things that later prompt the protagonist to action, things a character reads, hears on TV or on the Internet might have the same effect.

The most important part of believable decision making is making sure that the cause is in proportion to the effect. If all the character is trying to decide is where to go for dinner, a simple prompt, like knowing someone who owns a restaurant, is all that is needed. However, we’ve established that the best characters are often very unhappy with the situation they find themselves in, so the causes that lead them to accept and engage in that situation have to be much more significant.

The third part of believable characters is significant change to the character over the course of the story. If you’re sharp, you’ve already seen how these two tie together. While some changes are subconscious and gradual, sooner or later, when you realize how you’ve been changing, you have to decide if you want to try and go back to the way you are. This is sometimes called a “watershed moment”.

The term watershed refers to the way many small tributaries can join together and create a large stream or river. In the same way, characters face a significant moment of decision, usually just before the climax of a story. When your character reaches that moment of decision, all the influences that have put and kept your protagonist in their uncomfortable situation combine with all the things they have seen and heard along the way and we see the character choose to go from what they were to something new and better (or, in some cases, worse.)

As you build a character, it’s important to know what that watershed moment is, and how you want your character to decide it. And then you must gently push them toward that outcome. Not in a constant, steady advance, because that’s not realistic either. But when the time for the big decision comes, your readers will not find it believable unless you’ve shown them how it was arrived at.

This week’s example is Bob Parr, aka Mr. Incredible. We first get a look into Bob’s head as he struggles with his forced retirement from hero work. When he meets with Frozone, we’re told it’s because they know each other from the old days. When Bob gets fired we’re shown (literally) that it’s because he can’t stand a boss who won’t let him help people. When he’s offered the opportunity to do clandestine hero work, we see him gazing at his memorabilia before accepting. Bob’s watershed comes when, after nearly loosing his family, he comes to accept that they need to be present in all of his life, even his hero work.

So why does your character need to make a big decision at all? Well, that’s because it promotes something called character development. Put more simply, real people change over time. The only time we have to get to know your characters is in the context of the story or stories you tell about them. So, in order for your characters to be believable, they have to change in the course of their story.

Decisions and changes are closely related, so we’ve covered some of that ground already. But next week we’ll look more closely at what kind of changes we tend to expect, consciously or subconsciously, of a character.