Credibility (willingness to accept something as true in the characters and in their story world) must be meticulously nurtured in the literary story as an art form. Often credibility slips with illogical progression of plot ideas, or with poorly integrated character thoughts, actions, and words. Readers will fail to connect to a story where there is erosion of credibility, and the writing will not succeed. Even if the story requires suspension of disbelief–as all stories do to some degree–there is always a dependency on the absolutely logical association and progression of ideas for good writing.
Credibility in plot logic is the easiest to identify and discuss. As characters move through the story, choices are made for their action in the plot. Lazy or untalented choices will sink the story. For example, a prodigal son comes to the bedside of his dying father whom he has not seen since childhood. What happens next? He falls on his knees and weeps. He smothers his father to death with a pillow. He asks his sister to bring him a drink. He remains motionless, unable to feel emotion. And so forth. There are so many choices, but there is only one right choice for any one great story. An author finds that best choice after he or she seeks alternative after alternative. Most of these choices are made in the mind. But often an outline helps for timing and positioning, especially with critical story actions. Never take your first thought as your best, it rarely will be.
In characterization the credibility issue constantly lurks. It is a common error by an author that makes the reader reject and dislike the story—in varying degrees. You may think of credibility issues on two levels. First, the immediate. Is immediate story action, thought, reflection, or words of a character logical for that moment, and for what the reader knows about that character at that moment? Second, overall. Is the character developing in the story logically and along lines closely related to the theme of the story? Characters are chosen for a story by authors for (1) the capabilities of either having significant enlightenment about something or (2) for their potential of have significant change in their thinking and beliefs about something. As characters are developed, details and actions must be logical for how the characters will be irreversibly changed.
Credible emotional content in a scene must also be considered to match exactly what is needed for the story for the moment. Paradoxically, to create tension in the reader from emotions in the story, it is not sufficient to crank up the language with four letter expletives, two-word sentences and imperatives, and describe things as brightest and loudest. In fact, for best writing, worthy emotional scenes are created without emotionally charged abstract language (he was flooded by fear and love), but by terse clear concrete language and structure. The emotional valence of a scene must also coincide with what the reader will expect at any point in the story. Surprise is also a necessary component in storytelling, but the surprise must be credible too. To fail breaks the connection between reader and character that is necessary for good stories.
It may seem odd, but credibility need not relate to the reality of the reader’s world. Credibility is judged by the story world created by the author and told by the narrator. So a plot shift or a character decision set in 1929 needs only be credible for the story, and need not be credible for the reader’s time in existence. As the story is introduced, there is a contract of details established between author and reader–unstated of course–that continues to develop throughout the story and that will establish what is and is not credible.
There is a tendency for an author to dismiss consideration of credibility, but authors cannot afford to risk rejection of a story by a reader because of failure to address credibility issues. Successful story writing needs credible plot and characters for the story world that the reader can accept in their existing story world. This acceptance is, at least partly, humane character development through character change rather than just characterization that deals with description of the character before story begins.
In summary: for credibility, the final story product–novel or short story–must have reasonable thoughts and actions built on logical associations and progressions, total reader acceptance of timing and progression of story elements, and total believability that the emotional content of the writing matches the need for story development.