Among the three or four dozen pieces that Woody Allen has contributed to The New Yorker, the first one seemed to his editor, Roger Angell, to contain an overabundance of funny lines. He told Allen that even if the jokes were individually hilarious they tended cumulatively to diminish the net effect. He said he thought the humor would be improved if Allen were to leave some of them out.

Sculptors address the deletion of material in their own analogous way. Michelangelo: “The more the marble wastes, the more the statue grows.” Michelangelo: “Every block of stone has a statue inside it, and it is the task of the sculptor to discover it.” Michelangelo, loosely, as we can imagine him with six tons of Carrara marble, a mallet, a point chisel, a pitching tool, a tooth chisel, a claw chisel, rasps, rifflers, and a bush hammer: “I’m just taking away what doesn’t belong there.”

And inevitably we have come to Ernest Hemingway and the tip of the iceberg—or, how to fashion critical theory from one of the world’s most venerable clichés. “If a writer of prose knows enough about what he is writing about he may omit things that he knows and the reader, if the writer is writing truly enough, will have a feeling of those things as strongly as though the writer had stated them. The dignity of movement of an iceberg is due to only one-eighth of it being above water.” The two sentences are from “Death in the Afternoon,” a nonfiction book (1932). They apply as readily to fiction. Hemingway sometimes called the concept the Theory of Omission. In 1958, in an “Art of Fiction” interview for The Paris Review, he said to George Plimpton, “Anything you know you can eliminate and it only strengthens your iceberg.” To illustrate, he said, “I’ve seen the marlin mate and know about that. So I leave that out. I’ve seen a school (or pod) of more than fifty sperm whales in that same stretch of water and once harpooned one nearly sixty feet in length and lost him. So I left that out. All the stories I know from the fishing village I leave out. But the knowledge is what makes the underwater part of the iceberg.”

In other words:

There are known knowns—there are things we know we know. We also know there are known unknowns. That is to say, we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.

Yes, the influence of Ernest Hemingway evidently extended to the Pentagon.

Be that as it might not be, Ernest Hemingway’s Theory of Omission seems to me to be saying to writers, “Back off. Let the reader do the creating.” To cause a reader to see in her mind’s eye an entire autumnal landscape, for example, a writer needs to deliver only a few words and images—such as corn shocks, pheasants, and an early frost. The creative writer leaves white space between chapters or segments of chapters. The creative reader silently articulates the unwritten thought that is present in the white space. Let the reader have the experience. Leave judgment in the eye of the beholder. When you are deciding what to leave out, begin with the author. If you see yourself prancing around between subject and reader, get lost. Give elbow room to the creative reader. In other words, to the extent that this is all about you, leave that out.

Creative nonfiction is a term that is currently having its day. When I was in college, anyone who put those two words together would have been looked on as a comedian or a fool. Today, Creative Nonfiction is the name of the college course I teach. Same college. Required to give the course a title, I named it for a quarterly edited and published by Lee Gutkind, then at the University of Pittsburgh. The title asks an obvious question: What is creative about nonfiction? It takes a whole semester to try to answer that, but here are a few points: The creativity lies in what you choose to write about, how you go about doing it, the arrangement through which you present things, the skill and the touch with which you describe people and succeed in developing them as characters, the rhythms of your prose, the integrity of the composition, the anatomy of the piece (does it get up and walk around on its own?), the extent to which you see and tell the story that exists in your material, and so forth. Creative nonfiction is not making something up but making the most of what you have.

When I worked at Time, after at last escaping Miscellany I wrote for five years in a back-of-the-book section called Show Business. In a typical week, the section consisted of three or four short pieces probably averaging nine hundred words. After you finished a piece, it entered the system in a pneumatic tube. When you next saw it, it bore the initials of your senior editor. It also had his [sic] revisions on it. You left your cubicle, paper in hand, went to the senior editor’s office, and, in a mealy way, complained. Revisions might ensue. The piece then went to the managing editor, whose initials usually joined the senior editor’s without ado, but not always. At last, with both sets of initials intact, the piece went to a department called Makeup, whose personnel could have worked as floral arrangers, because Time in those days, unlike its rival Newsweek, never assigned a given length but waited for the finished story before fitting it into the magazine.

After four days of preparation and writing—after routinely staying up almost all night on the fourth night—and after tailoring your stories past the requests, demands, fine tips, and incomprehensible suggestions of the M.E. and your senior editor, you came in on Day 5 and were greeted by galleys from Makeup with notes on them that said “Green 5” or “Green 8” or “Green 15” or some such, telling you to condense the text by that number of lines or the piece would not fit in the magazine. You were supposed to use a green pencil so Makeup would know what could be put back, if it came to that. I can’t remember it coming to that.

Groan as much as you liked, you had to green nearly all your pieces, and greening was a craft in itself—studying your completed and approved product, your “finished” piece, to see what could be left out. In fifty years, The New Yorker’s makeup department has asked me only once to remove some lines so a piece would fit. The New Yorker has the flexibility of spot drawings to include or leave out, and cartoons of varying and variable dimensions, and poems that can be there or not be there. Things fit, even if some things have to wait a week or two, or six months. Greening has stayed with me, though, because for four decades I have inflicted it on my college writing students, handing them nine or ten swatches of photocopied prose, each marked “Green 3” or “Green 4” or whatever.

Green 4 does not mean lop off four lines at the bottom, I tell them. The idea is to remove words in such a manner that no one would notice that anything has been removed. Easier with some writers than with others. It’s as if you were removing freight cars here and there in order to shorten a train—or pruning bits and pieces of a plant for reasons of aesthetics or plant pathology, not to mention size. Do not do violence to the author’s tone, manner, nature, style, thumbprint. Measure cumulatively the fragments you remove and see how many lines would be gone if the prose were reformatted. If you kill a widow, you pick up a whole line.