Part 3: Action-reaction in fiction as Newton’s Literary Third Law

“For every action, there is an equal and opposite reaction…” Newton’s Third Law, thus stated, uses the words action and reaction to refer to the physical forces operating on two interacting objects. These forces exist simultaneously (equal magnitude, opposite direction), as in the image below.


*** Be forewarned: The writing analogy strays from the simultaneity implicit in Newton’s Third Law. ***

In WriterSpeak (with a little simplification), Newton’s Third Law could be translated as follows: “Every (protagonist) action sparks an opposing (antagonist) reaction.” Conversely, each enemy attack creates some situation to which the hero must respond.

Why? Not necessarily because the antagonist is a bad person (he may not be a person at all), but because he and the hero have clashing goals (e.g., The Fugitive‘s Dr. Richard Kimble vs. Deputy Samuel Gerard).

Dr. Richard Kimble (played by Harrison Ford) professes his innocence and Deputy Samuel Gerard (Tommy Lee Jones) says, “I don’t care.” (But guess what. He cares.)

On a basic level, the central conflict of every novel is founded on this tug-of-war interaction between a hero and his opposition. The antagonist acts (cause). The hero reacts (effect). For every action taken, some change occurs that invites further response. Plot is, by definition, a sequence of events linked by action and reaction—by cause and effect. (More on that here.)

On a large scale, we can see this basic tug-of-war structure across Star Wars episodes 4 to 6. In A New Hope, the rebels destroy the Death Star. (Hero victory!) But then The Empire Strikes Back. (The hero withdraws to lick his wounds.) Finally, in Return of the Jedi, hero Luke not only overcomes the antagonist (Darth Vader), but also rescues him from the dark side. (Permanent victory! The central conflict is resolved.)

Back and forth like lumberjacks moving a two-person saw, the hero and villain push and pull, perpetually digging in deeper. It’s not always as straightforward as hero vs. villain, but the point is, your hero isn’t working in a vacuum (er—unless you’re writing sci-fi). But even if he is in a literal vacuum, it’s not clear sailing to the finish. He’s dodging space debris where there should be a planet, getting caught in a tractor beam, and being diverted into smelly garbage mashers by a pushy princess (all because he’s coming up against that antagonistic force).


Motivated by some personal need, the hero presses forward in pursuit of his goal. That goal is what’s driving him forward. But he must meet with opposition or else the story sags. After all, opposition stems from that all-important ingredient of good fiction, which finds its origin in that action-reaction push and pull: Conflict!

What do you think? What are the forces of antagonism in your own story? Do you enjoy a story more when the antagonist is blatant (as in Star Wars and Silence of the Lambs) or when it’s more subtle (as in The Help or Forrest Gump)? Leave a comment below (and drop your email here) for a chance to win a 2500-word critique or an e-copy of Janice Hardy’s book Understanding Conflict. To enter the “special giveaway” with the option of winning a $25 gift certificate from Better World Books, visit the permalink here and follow the instructions.

Missed the first two? Check them out here: Part 1: How Newton’s First Law mimics character motivation. AND Part 2: How a character’s internal change mirrors Newton’s Second Law.