Fiction often dances on the line between the incredible and the realistic. Keeping a story contained within the confines of what is credible—possible, likely, normal, conventional, ordinary or REAL—is not as easy as it sounds. First, the characters rarely cooperate, because the more realistic the character the more likely they are to have beliefs (dreams, delusions, or fantasies). Like real people, well-drawn characters are complex—and hard to write!
Every once in a while I read a novel with a character described as logical. These hyper-rational creations are often felled by an encounter with some element of magic—they meet a ghost, solve a mystery with an unexpected intuitive leap, find themselves stumbling into an incredible place, or experience a transformative religious revelation. Fiction doesn’t tolerate the lack of realism of the hyper logical.
Even Mr. Spock—the quintessential rational character—is most interesting when he is confronting his human emotions. For years my favorite episode of the original series was ‘The Naked Time.’ That’s the one where a mysterious virus infects the crew and emotions overrun their trained, disciplined, and organized rational minds. Spock has a hard time in that episode!
Writing credible characters means incorporating some level of irrationality into the personality of a protagonist. It keeps them balanced and helps avoid the cartoonish personae of one note super heroes. I’m not saying that each character has to have a nutty streak, but they have to have some kind of imperfection in order to make them read as credible.
This is where it gets tricky.
I’ve read all too many mysteries where each character is given a “quirk” or “glitch” or “fatal flaw” that becomes their defining characteristic. He’s brilliant, funny, and attractive, but he has a barely controlled addiction, and could easily slip back into self-destructive behavior. She brilliant, funny, and attractive, but she suffers from low self-esteem that leaves her vulnerable to her need for external praise and affirmation—oh, and she lives with five dogs or six cats or an iguana. The characteristics meant to make them human turn the characters into amalgams of glitches & quirks, because by the end of the novel one characters has drunk enough coffee to fuel an army of insomniacs and the other has tried on multiple outfits each time she has to confront a stressful situation.
It’s the subtle irrationalities, the small deviations, the blind spots, and the minor eccentricities that add a dash of reality. A list of quirks is a list of quirks—not a personality.