Why? Because? Because Why? Because I Say So.

Sir Isaac Newton was a physicist rather than a dramatist, but his observations about forces in motion stand up as well in the art of drama as they do in the science of the behavior of matter.  Consider:  For every action, there is a reaction that is equal in force and opposite in direction.

Writers have been taking the tangible results of that observation to the bank or the grocery store or the corner pub since before written language, before movable type, before the days when writers and actors had any thought about payment for their efforts.

Activity causes a tangible response.  You spend long enough digging a hole or working on a story, you're on target for a backache.  You dig the hole in the wrong place or make the story reflect some aspect of the human condition too painful for most in the audience to process and the likelihood increases for you to come away with a headache.  

One example is sufficient to illustrate the point:  In 1899, a writer of stunning insights and narrative technique produced a novella called The Awakening, published to uniformly negative reviews.

Not only was this a demonstration of action producing a reaction in physical terms, as well, The Awakening triggered a set of responses among some women readers that transferred itself across the generations, influencing stories to come and personal behavior.

In E. M. Forester's Aspects of the Novel,  one of the early--and best--books about the physics and mechanics of the novel, Forester had insightful things to say about the dramatic force he referred to as causality.  Things do not happen in haphazard randomness; they happen because of earlier actions taken--or rejected--by a character.  One forceful writer managed to demonstrate both the action taken and the action declined in two works that have long outlived him and will no doubt continue to do so.  

The longer of the works presents us with a character who recognizes his fast-approaching state of depression, prompting him to something he;s done before under such circumstances.  He signs aboard a ship as an able bodied seaman.  For his reward, the captain of the ship, The Pequod,  turns out to be a megalomaniac.

Herman Melville's short, pithy account of a character who acts by refusing to act, Bartleby the Scrivener, is in its way as disturbing as Moby-Dick.  Wherever we, or you, turn, literature does not begin with an eruption of spontaneity; it begins with a character who wants something, wants it now.  That desire is enough to provoke the character's quest or someone else's questions and probing to the point where the character under examination responds.

If a work of dramatic narrative lacks the inner quality of causality, it cannot be considered story because of the way story has evolved as an individual on some quest or having made some discovery.  The short, pungent short story by Tobias Wolff, "Bullet in the Brain" provides an excellent example of how the short form has evolved over time.  A book critic enters a bank to make a deposit, a quest not significant for being extraordinary.  Fate and the author have conspired to address that matter.

The protagonist is already growing impatient with the persons in line ahead of him and the time needed to complete their transactions when we learn in no uncertain terms that the bank is being robbed.  One of the bandits is every bit as impatient as the protagonist, who is arrogant enough, foolish enough, and sarcastic enough to begin laughing.

How easy is it to observe how story is strands of relevant detail, wound about the armature of causality?  Quite easy; each wrap of detail begins to push the resulting dramatic payoff toward an acute goal.

A detail within a story needs to have somewhere in its fanny pack a measure of causality, the ability to precipitate, if not directly cause, the next action.

When you think about such things, you can't help wondering what kind of storyteller Sir Isaac would have been, and you take the matter even farther on occasion by keeping his observations in mind as you consider the options before characters of your contrivance.  

Objects in motion, Sir Isaac observed, tend to stay in motion, until they are confronted by a force greater than their velocity.  We know what that force is in physics.  Inertia.  In dramatic writing, we call that opposing force such things as description, explanation, and that most oppressive inertia of all, defensiveness.