Long ago, when I was taking my first uncertain steps as a writer, a successful and much older novelist told me, by way of instruction, “Fiction is shorthand.” I didn’t quite grasp her meaning, but over time the truth of this beautiful reduction became clearer and clearer to me, until I had embraced it as gospel.

I was reminded of it recently when I opened Francine Mathews’ political thriller, Too Bad to Die, and came upon this masterful sentence on page 4: “She turned her back to the window—her gorgeous, supple, peach-flushed back—and stared at herself in the mirror.”

The character is Pamela Churchill, Winston’s daughter-in-law, and she’s an enchantress with a penchant for expensive clothes, intrigue, and seduction. Ms. Mathews describes her further—her hair color, her eyes--but that first sentence would be enough. Her gorgeous, supple, peach-flushed back--the image evokes her in our mind’s eye. She appears to us full-blown, and the rest of her is as lovely as her back.

Choose the telling details that stand for the whole. Think of it as enlisting the reader’s imagination to finish the job you’ve started. Give a young man a ponytail, and a face comes to mind. A woman in a halter top with scarlet lipstick and bleached blond hair is probably instantly recognizable. “Miss Barkley was quite tall,” writes Hemingway in A Farewell to Arms. “She wore what seemed to be a nurse’s uniform, was blond and had tawny skin and gray eyes. I thought she was very beautiful.” The effectiveness of these details is in their simplicity; they function as triggers to the imagination, and in the time it takes to read them Catherine’s face and figure have become vivid to us.

Describe places—a landscape, a front yard, a building, a room—in the same careful way. You can’t enumerate every item of furniture in the Hollywood mogul’s Beverly Hills living room; which ones are definitive? An original Picasso over a fieldstone fireplace and an Italian leather sofa might be all you need. I’ve found mustard-yellow paint on walls or trim to be useful shorthand for urban dilapidation and poverty. A torn, age-yellowed window shade, cracked linoleum on the floor, can define an apartment. A brick house with a pillared porch, groomed lawn, azaleas, a rose bed: got it.

Good dialogue, in its succinctness and compacted meaning, is shorthand. When I teach dialogue, the first point I make is that dialogue in fiction is not at all like dialogue in real life. The dialogue writer is not a stenographer, taking down what he hears; he’s an extrapolator, a rewrite man, condensing what we say and giving it shape and cohesion. Where your daughter might have spent five or six sentences explaining why she was out till two in the morning, the girl in your novel gets three sentences, max, and preferably one or two.

Dialogue can’t wander, and any repetition—we repeat ourselves constantly in real life--must be intentional on your part, for effect. Good dialogue is relentlessly direct. Think of it as what is left when extraneous verbiage is stripped away. It is what we mean to say, what we do say, in essence—shorthand that preserves the most expressive and succinct lines of an exchange or conversation.

Good dialogue sounds real, of course, and here’s the paradox of shorthand in fiction. The better the dialogue, the less realistic it is likely to be, and the more realistic it will sound. Its color, its undeviating relevance, its compressed emotion, give it an authenticity that seems self-evident.

Less is more,” another writer once said to me. The art of fiction is in the power of suggestion. The abbreviated description of a person or place—those few well-chosen details—lights the reader’s imagination, where that woman with the creamy back, or that country road at sundown, are more vivid than words alone can make them.