EVERY MORNING between 5 and 5:30 Gene Wolfe sits down at one of his two IBM typewriters. Before he goes to bed that day he will have written five pages. "Usually it takes between an hour and a half and three hours," he explains over the phone, but sometimes he's still working at midnight.

In itself this may sound like a lot of work--even before you realize that Wolfe also puts in a full day as a senior editor at Plant Engineering Magazine in Barrington, Illinois, a Chicago suburb. There he edits, buys some 25 free-lanced articles a year, and writes a major cover story every few months. "The latest," he says, "is the first in a series on industrial robots."

Such disciplined energy recalls that of the great but often slapdash Victorian novelists or of many writers of pulp science fiction. In fact, Wolfe is nothing if not an artist, a perfectionist. Every one of his carefully wrought stories and novels undergoes at least three drafts, occasionally as many as 10. "I write to please myself. I try to write what I myself think a good book, one that satisfies me. Until I mail a manuscript out I'm never sure that I'm through with it."

In The Book of the New Sun Wolfe has certainly written a book that many people will be satisfied with. "It's gotten a greater readership than I anticipated. And I'm happy about that." Wolfe is as modest as he is painstaking, for his four-part novel about the adventures of the torturer Severian on far-future Urth has been called "one of the two or three best-written books in the field of science fiction ever" and "a major landmark of contemporary American literature."

Born in 1931, Gene Wolfe grew up in Texas, where his father was a restaurateur and small businessman. After attending Texas A&M and dropping out because of poor grades, Wolfe found himself drafted into the Korean War. He served as a private, earning the Combat Infantry Badge. After the service, Wolfe returned to Texas A&M on the GI Bill, received a bachelor's degree in mechanical engineering, and soon married a childhood friend. While working in research and development for Procter & Gamble in Ohio, the young engineer thought he might write some stories.

"If you have a wife and four children, as I do, you tend to be scraping around for ways to make a bit of additional income. I started trying to write in late 1956 or early 1957, hoping to earn enough to buy some furniture --but it was about 1963 before I got anything published. Most of those early stories were pretty bad. I just hadn't learned how to write fiction. I had to start by trying to figure out which end of the fiddle you stick under your chin. And eventually how to play it." In 1967 Damon Knight--a mentor to many contemporary science fiction writers-- published Wolfe's third story and the engineer realized with a sense of epiphany that he'd become a writer. "That's what I meant when I dedicated The Fifth Head of Cerberus to Damon in memory of when he grew me from a bean." Since then, Wolfe says quietly, "I've sold about a hundred stories." They range from technological science fiction to complex psychological studies, and include the comic, sentimental, and macabre.

"You don't in my experience have an idea for a story. You have several different ideas you are nurturing or trying to shove out of your consciousness. Eventually out of the crowd of a dozen or so perhaps three or four seem as though they might work together in one book. That's the way it was with The Book of the New Sun.

"I wanted to do the grave-robbing scene that kicks off The Shadow of the Torturer, that scene in the cemetery with the people pulling the corpse up out of the ground. I also wanted to do a book about a torturer, the kind who is running the dungeon in all those old cartoons, to put myself in his shoes. I enjoy writing about people who are generally considered bad guys. That is I take heroes who are villains and try to show things from their standpoint." (One of Wolfe's best-known tales, included in The Island of Doctor Death and Other Stories and Other Stories, carries the title "The Hero as Werewolf.")

As for the tetralogy's setting--a future earth, spinning beneath a red sun, mingling science, mystery, and the medieval--Wolfe says forthrightly "I don't think there's any question that I've been influenced by Jack Vance." At the beginning of a new collection of essays, The Castle of the Otter (Ziesing Brothers Publishing, 768 Main St., Willimantic, Conn. 06226, $16.95), Wolfe recalls that at one period in his life Vance's elegiac, marvel- filled novel The Dying Earth was for him "the finest book in the world."

Still, there are other influences. "A friend of mine told me that the tone of The Book of the New Sun reminded him of Robert Graves' I, Claudius and Claudius the God, and immediately I saw that he was right." Severian's voice--measured, serene, precise--contrasts with his story's complex twistings back and forth through memory and with the ornate, not quite familiar words of his society: cacogen, psychopomp, fricatrice, fuligin. None of these is made up.

"A lot of them I'd come across here or there, just noticed them. I went through lexicons, dictionaries, and whatnot, and traced down leads when I thought I needed an odd word. When I started the book I remembered Jim Blish"--one of science fiction's best writers and critics--"having said that on too many planets you find a rabbit and it's called a smeat. And it's obvious that the author is thinking of a rabbit--just as Lorne Greene on Battlestar Galactica used to think of a space ship as an aircraft carrier. You could tell. Anyway it occurred to me that earth really had enough odd words to describe odd things and I didn't have to make up any.

"As for the names, I largely looked for real names with sounds that seemed appropriate to a character I had in mind. Severian suggests both sever and severe."

Surprisingly, the now-pervasive religious theme developed later in the book's seven years' writing. "Sometimes you start with a small idea and it grows," remembers Wolfe. "I put religion into The Book of the New Sun because I tried to put in just about everything I thought important in human life. You know the story about Leo Tolstoy the night after he sent the manuscript of War and Peace to his publisher? He is supposed to have sat up in bed, slapped himself on the forehead and said: 'My God, I forgot the yacht race.' I don't have a yacht race in The Book of the New Sun, but I tried to talk about children, war, love and death, God, heaven and hell and all these things that are really pivotal to the human condition. I would like to have put in a lot more that I couldn't manage. Music for instance."

The Book of the New Sun may not have music or a yacht race, but it seems to contain everything else: myths, folktales, poems, a miracle play, marching songs. Severian encounters figures from every class of society, including various partly human characters. At one time he journeys, unsuspectingly, with a robot, a giant, a bionic woman, a homunuculus, and a revived corpse-- all of whom readers come to care about deeply.

Such exuberant invention explains why Wolfe admits "my favorite author is Dickens. I also like Kipling. Moby-Dick. And Oscar Wilde's fairy tales--no pun intended. Once Damon Knight asked about writers or books that had influenced me and I said J.R.R. Tolkien, the much neglected G.K. Chesterton, and the standard handbook of mechanical engineering." Engineering? "I think engineers have a better feel than most writers for the difficulty of developing new machines, new devices, and for the rate of speed at which such technological advances occur."

Wolfe's attention to style, his employment of demanding formal structures--"I love obliquity"--and his psychological acumen also link him to some of the contemporary science fiction writers he most admires: Ursula K. Le Guin, Thomas M. Disch, R.A. Lafferty. All of them shuffle uneasily under the science fiction rubric.

"I don't hold much with categories, really," says Wolfe. "They're for publishers and booksellers. I simply try to write the best story I can. People who condemn a particular genre, whether science fiction or mysteries, really can't know what they're talking about. Its as though I were to say all movies are bad. . . . I know that science fiction is dismissed by a lot of people, but I don't believe its dismissed by very many readers."

At the moment Wolfe is hard at work as usual. "After I finished the first draft of The Urth of the New Sun, a kind of coda to Severian's story, it seemed a good time to work on a couple short stories that I'd promised people. That was what I was doing this morning. In fact, I was working on both of them."

Will there be any more novels about Severian's world after The Urth of the New Sun? "I don't know," answers Gene Wolfe, "but I suspect that will be it. I don't like to repeat myself."