Once upon a time, I thought that IQ was the most important attribute of human beings. Three decades ago, I came to believe in God and began to understand the centrality of what could be called SQ, spiritual quotient. In recent years, we've rightly heard more talk of EQ, emotional quotient.

But in our land of opportunity, one more Q factor is crucial: This is DQ country, and by that I mean not Dairy Queen, but Determination Quotient. Determination pays off differently depending on our starting point -- for a poor immigrant, it may lead to not affluence for himself but a better life for his children -- but it's key in making sales, winning pennant races and (I'll write about something I know) writing.

Tom Clancy isn't the greatest stylist around, but he presses toward his goal, so his advice is worth remembering: "Writing is most of all an exercise in determination." So are the high-DQ words of two other craftsman-authors, Michael Crichton ("Books aren't written. They are rewritten") and James Michener ("I'm not a very good writer, but an excellent rewriter"). One of America's top stylists, E.B. White, noted that, "A writer who waits for ideal conditions under which to work will die without putting a word to paper."

A book of interviews with top non-fiction writers, Robert Boynton's "The New New Journalism" (Random House, 2005), lays out more evidence of the relation of inspiration to perspiration. For example, Richard Ben Cramer (author of "What It Takes") comments that he once read Tom Wolfe and thought, "God touched you and made you a genius, and that's the end of it." Then he saw Wolfe toiling at a desk, writing: "I looked in his eyes and saw the haunted, hunted animal look."

And here's the testimony of "Moneyball" author Michael Lewis: "The most common pleasant thing people say to me about my writing is that it looks 'effortless.' ... It is the opposite of effortless. ... I probably do 20 drafts of each chapter. I write something over and over. It's like "Groundhog Day." My writing process is sweaty and inelegant."

(He also notes, in response to a question about whether he needs to write in one particular place, "I've written in awful enough situations that I know the quality of the prose doesn't depend on the circumstances in which it is composed. I don't believe the muse visits you. I believe that you visit the muse. If you wait for that 'perfect moment,' you're not going to be very productive.")

So it goes with other excellent writers. William Finnegan acknowledges that he'll produce "15 or 20 drafts." Alex Kotlowitz admits that once he's developed a first draft, "I go back and rewrite, scene by scene, detail by detail." Susan Orlean says: "I hate going out to lunch because that is exactly when I am usually getting up a head of steam. So I usually just grab a sandwich and eat at my desk. ... Rather than taking a break because I can't get anything done, I take a break whenever I write something that I feel really good about. It is hard for me to stop for dinner and then go back to work, so I often stop writing around 8 p.m."

High-DQ Americans find ways to take a vacation from one project not by lying around, but by adding the stimulation of another project. Michael Lewis: "At any given moment, I have at least four projects underway. I write short columns ... I'm usually working on a book ... I'm usually at some stage of one of the long articles I write. ... I don't know whether it is a character flaw, or just comes with the life of a freelance writer."

No, it comes with a high DQ, in writing or in any other area of life.