Plots and Causal Chains

The idea that a plot is a series of events related by cause and effect goes back at least to E.M. Forster, who said, in Aspects of the Novel, that “The king died and then the queen died” was not a plot, merely a set of sequential events, but “The king died, and then the queen died of grief” was a plot because the first event causes the second. Obviously, most novels need a much longer causal chain than that.

Let me pause for a minute to define what a causal chain is and does, in terms of fiction. A causal chain is just what it sound like: a series of events, each of which logically causes the next thing in the chain to happen. In its simplest form, it can look something like this:

Protagonist needs money -> Protagonist steals dragon egg to sell -> Enraged dragon attacks protagonist’s village -> Protagonist’s family killed by enraged dragon

It’s very like knocking over a chain of dominoes. A really complicated chain of dominoes. If you break the chain – if the cause isn’t strong enough for the effect or vice versa – the plot falls apart.

What a causal chain does in fiction is, it binds the scenes and chapters together. A series of totally unrelated events is not a story: “George’s dog dies. Amelia Earhart’s plane disappears. Susan’s car gets a flat tire. The rabbit stew burns. An asteroid hits the outpost on Mars.”

That all sounds straightforward enough, but it isn’t as simple as it seems. Causal chains in most novels operate on two levels, the plot level and the character level. To put it another way, both the plot logic and the characterization logic need to hold together in their own “A causes B which causes C” fashion. If the character logic doesn’t work, the plot logic falls apart, and vice versa.

For instance, the enraged-dragon story above won’t work if the protagonist is established up front as a total coward who just wants money to show off. Readers aren’t likely to believe that he/she would have the nerve to steal a dragon’s egg. Similarly, if dragons in this world are r-strategy reproducers – if they lay hundreds of eggs, like frogs, and expect most of them to fail to make it – then readers aren’t likely to believe that the theft of one egg would cause the dragon to become enraged.

The second complicating factor is that causal chains can loop and branch, becoming more like a net or a web than a straight line. The hero’s visit to the gay bar provides a lead in the murder, but also causes his girlfriend to be suspicious, his mother to freak out, and the villain to take steps to murder him. The protagonist isn’t rescued from the un-escapable dungeon by a random stranger; they’re rescued by the companions they’ve collected/rescued in the previous ten chapters. The “cause” of the rescue is spread out over a bunch of previous scenes that establish friendship, loyalty, skills, etc.

Every scene and every chapter in a story has a reason for being there – there’s something about the story that would break if you took it out. Sometimes it’s the plot level that would fall apart (if Protagonist goes to work for the lumber mill instead of stealing the dragon’s egg, there’s no reason for an enraged dragon to attack the village); other times it’s the character/emotional level that would fall apart (if Janet doesn’t have tea with the Queen, Elizabeth won’t have anything to be jealous about and there will be no reason for the big fight between them).

Ideally, every scene would create a link in both causal chains; Janet having tea with the Queen would cause Lady Lamb to invite her to the ball where she meets the villain, and also cause Elizabeth’s jealousy and the fight. Realistically, some scenes work only on the emotional/character causal chain, and others work only on the plot. Keeping the one-offs to a minimum is usually a good idea, unless you are consciously going for a mostly-one-level story.

The other thing to watch out for is the looping and branching. It is extremely easy for writers to wander off down an interesting branch-chain and forget about what they really wanted to do with this story and/or where they were going. Sometimes, this works out well (especially if one’s natural writing process is pantsing), but even if it goes somewhere interesting, it generally involves lots of cutting and rewriting to make the central causal chain follow the new direction to the new ending.

Highly analytical writers often don’t have a lot of trouble creating solid causal chains (though they frequently stall for a while trying to figure out the plot-logical next link, if they didn’t plan ahead). More intuitive writers may need to double-check periodically to make sure they don’t have any breaks in the chain – that shopping scene that was such fun to write but that really doesn’t follow from anything earlier and that also doesn’t lead to anything later, for instance.

The important things to think about when you’re testing your causal chains are “why” and “because.” The dragon attacks because in the last scene prior, the protagonist stole the dragon’s egg. Also, you want the cause and the effect to be commensurate with each other. Stealing from a dragon’s hoard, or stealing its egg, seems like enough to enrage the dragon and cause an attack on the village; leaving picnic litter half a mile from the entrance to the dragon’s cave doesn’t seem like enough to provoke such a reaction.

There are things besides causality that can tie story events together, but most of them are much weaker than a causal chain. The most commonly used is probably chronology: this happened, then that happened, then something else happened.