Of all the architectural elements in the fiction writing process, plot is the primary scaffold. Without it, there is no story. There are some writers who begin with characters and evolve a plot from them, but it all has to come down to plot.

I'm fairly new to the writing process myself, but I'm an old analyst, steeped in software tech, and lately I've been contemplating what it is about plot, the way it's used by writers, that makes it special. Why do people struggle so much with it?

I'm not sure what “writer's block” really means as it's commonly described. When I'm not writing when I should be, it's almost always because of external factors (stress, depression, etc.) Only rarely have I been able to pin it down to the work itself — when I've produced a scene in first draft, and something about it feels false to me, I can't continue until I resolve the problem.

My analytical brain has been chewing on what's going on when that happens.

Let's say you're out in the jungle, in a state of nature. That swaying bush might mean a tiger, and your stone-tipped spear is looking mighty small. Your mind begins racing. What if it's a dangerous animal? If it moves toward me, which of these trees looks easy to climb, and can it follow me? Could I maybe run far enough away if I start now? Maybe I could throw down the small animal I've just killed, and distract it from following me. Or maybe I could push my hunting companion in front of me, as an alternative bait. What if I'm wrong about the tiger, how would I explain that action to my companion? Would my reputation suffer? What else could that rustle be, if it isn't a tiger… And so on. You could spin out dozens of these alternative scenarios and, under sufficient adrenalin motivation, they would all flash before your eyes for review.

When you dream about the incident tonight (assuming the tiger didn't eat you), ever more fantastical alternatives will present themselves.

This is a fundamental survival skill in humans, the ability to take known elements about how the world works and extrapolate from them a variety of scenarios for what might happen next. The humans who did this more accurately survived, and we have very well-tuned skills in this area. We know what a tiger would do, what our running abilities are, what our companion might do, and so forth.

When we make up worlds, when we write fiction, the same rules apply. We can't help but extrapolate from the known elements to a cloud of possible “next steps” in the plot. We can accept fantastical elements that have no counterpart in the real world (what comes out of the bush isn't a tiger but an alien) and invent scenarios from there.

But what we can't accept are inconsistent behaviors in known elements. I know what a tiger might do, I have a mental model of it that is consistent and based on observed behavior. I don't know that about an alien, but if I observe well enough, I will make a model of its behavior over time, and that will get it done for me — I can add it to my repertoire. Like any other scientific observation, if its next action violates the predictions of my model, then I must improve my model until it accounts for all observations.

The key word in this is consistency. If a character's behavior is inconsistent with its model, and that can't be reconciled by additional facts to form a fuller model (which is the same as saying it exhibits arbitrary behavior), then I can't believe in it — too much cognitive dissonance. (One effective means of psychological torture is for the practitioner to deliberately cultivate arbitrary, unpredictable behaviors toward his victim.)

When writers talk about characters driving the plot in unplanned directions, this is what's happening.

When I'm chewing on a plot problem, my subconscious is good at suggesting what might happen next. My characters are known entities and can only behave in certain ways. If I want one to behave unexpectedly, I have to change his model by giving him a more detailed background that would support a different behavior.

If I write a scene that feels false to me, the falseness comes from the violation of a character's model. “That character would never do that” is what we say when that happens. The falseness stops me in my tracks, and I have to change the plot to accommodate it, or support an expanded model of the character by earlier detail.

In other words, I have to improve the materials that drive my plot, or change it to accommodate my available materials. Like any building project.

What would happen if I were to insist that the plot must drive the characters, instead? Bad things… We've all read the mystery and suspense novels that result when plot overrides plausible behaviors.