I HAVE SOMETIMES THOUGHT about the books a kingly uncle ought to put into the hands of a young person who wishes to become a writer. Naturally, any aspiring writer should study the Bible, Shakespeare and other such classics. But the books I mean are those that hint at the actual processes of the imagination, or strip away the tweed jacket and pipe to reveal the writer for what he is -- a blacksmith of language, forging sentences with hard, painstaking labor. In such instances, Keats' letters of James' prefaces and notebooks always come to mind, as do Virginia Woolf's diaries, James Agee's letters to Father Flye, and any good life of the supreme hack, Samuel Johnson. But for me the correspondence of Gustave Flaubert soars above all other works in setting forth the proper ideals and accompanying rigors of art.

To most Americans Flaubert is probably little more than a patch memory of Madame Bovary, the Silas Marner of introductory college French lit courses. But should Flaubert be more than a name, it is in large part due to the efforts of Francis Steegmuller, who now caps his career as a Flaubertiste with a translation of The Letters of Gustave Flaubert. Those readers familiar with Steegmuller's "double portrait," Flaubert and Madame Bovary (first published in 1939), or his more recent compilation, Flaubert in Egypt, know how extensively he has drawn on the letters -- and how well he has already translated many of them in these earlier works. This thoughtful selection from the correspondence renders every phrase exactly and memorably, as befits the martyr of the "mot juste," this saint of the religion of art. From its forthright Englishing of Flaubert's bawdy to the gracefulness of Steegmuller's connecting commentary and the handsomeness of the book's general design, The Letters of Gustave Flaubert is a treasure.

This first of two volumes focuses on Flaubert's growing obsession with writing, his travels in the Near East and the composition of Madame Bovary. Flaubert was early caught up in the fervor of a vision, which he proselytized to his correspondents and which he tried to realize in his work. "I envision a style," he wrote at the outset of his career, "a style that would be beautiful, that someone will invent some day, ten years or ten centuries from now, one that would be rhythmic as verse, precise as the language of the sciences, undulant, deep-voiced as a cello, tipped with flame: a style that would pierce your idea like a dagger, and on which your thought would sail easily ahead over a smooth surface, like a skiff before a good tail wind."

He spent his life pursuing that almost chimerical ideal, and in the process transformed novel writing from an amusement into a vocation. His letters chronicle his nightly devotions -- "Last week I spent five days writing one page" -- and have been justly called the bible of art for art't sake.Andre Gide kept a collection of them by his bedside; Henry James spoke reverently of their author as the novelist.

Born in 1821, Gustave Flaubert was the son of a highly respected Rouen surgeon, whose wise investments insured that his son would never have to live by his pen. From an early age the boy wrote easily, turning out plays, stories and short novels, all of them vaguely romantic and effusively lyrical. (The best early work, Novembre, treats a young man's love for a prostitute.) For a while Flaubert halfheartedly studied law in Paris, but following what appears to have been an epileptic seizure, he abandoned any thought of a worldly career for the more contemplative life of art.

His first novel that he thought publishable was La Tentation de Saint Antoine, a guady, phantasmagoric prose poem, based on a Brueghel painting that depicted the various temptations of the ascetic hermit. Flaubert's two best friends advised him to throw it into the fire. (He didn't: he was to return to La Tentation twice more, seeing in the saint's life a reflection of his own.) Depressed and uncertain of his vocation after this setback, Flaubert accompanied one of these friends, Maxime DuCamp, on an 18-month trip through the Near East.

In the "Orient" the young writer discovered an oasis of erotic satisfaction, a land of "luxe, calme et volupte." In letters home he describes the waters of the Red Sea carressing his body like "a thousand liquid breasts"; he watches a famous courtesan perform the erotic Bee dance and sleeps with her amid the cockroaches. He even claims to have sodomized an Egyptian bath boy. "It made me laugh, he wrote his other friend Louis Bouilhet, "that's all. But I'll be at it again. To be done well, an experiment must be repeated." But even while sexually distracted the would-be novelist records the smallest details -- a dancing girl's bad incisor, a speck of sand in the eye of a young whore.

When Flaubert returned from Egypt, the now 30-year-old writer took up again with his mistress Louise Colet, a Parisian woman of letters, and soon afterwards plunged into the 4 1/2-year composition of Madame Bovary (whose plot was suggested by a provincial case of adultery and suicide).

In his almost daily letters to Louise, scribbled in the morning after a night of writing and revision, the young novelist hammers out his philosophy of art. "There are no noble or ignoble subjects," he writes. "From the standpoint of pure Art one might almost establish the axiom that there is no such thing as subject -- style in itself being an absolute manner of seeing things." Louise, as a poet, counters with the claims of romanticism, that art should be an outpouring of strong, personal emotion. Flaubert answers disdainfully that "an author in his book must be like God in the universe, present everywhere and visible nowhere."

When not discoursing about the impersonality of art, Flaubert dwells on sex, the other great theme of the letters. "I wish to gorge you with all the joys of flesh," he writes to his mistress, "until you faint and die. I want you to be astonished by me, to confess to yourself that you had never even dream of such transports." (Despite this gusto, he becomes as fearful as an adolescent when "the redcoats" fail to arrive on time). The correspondence constantly documents the close relationship, often antithetical, between sex and art, between the urge to procreate and the wish to create. A night of writing resembles a stretch of violent lovemaking. Spending his energies on a woman takes away his energies for art. Although he tells Louise that he dreams of the roundness of her breasts, instead of traveling to Paris for a rendezvous, he pumps her for information about the reading of romantic young girls, using her as a source for his heroine's psychology as Joyce would use his wife Nora for Molly Bloom's. "Love," he wrote, "is only a superior kind of curiosity."

While staving off the sexual demands of Louise, Flaubert spent his nights with Madame Bovary, taking three months to compose one scene, shouting out his phrases over and over, testing their balance. "A good prose sentence should be like a good-line of poetry -- unchangeable, just as rhythmic, just as sonorous." Even the alteration of a single word, he explains in one letter, disrupts the unity of several pages. Each Sunday his friend Bouilhet would go over the week's work with him, criticizing epithets, pointing out deficiencies in the dialogue (Flaubert much preferred indirect discourse), compelling him to rework his outline, in all ways playing Max Perkins to his Gallic Thomas Wolfe. Within a short while Flaubert loathed the book, began to label it a mere exercise. His niece Caroline, then a little girl, believed that "Bovary" was a synonym for work, since her uncle always gave a sigh and kept saying that he had to get back to his Bovary.

Yet even as he grew disgusted, he refused "to hurry by a single second a sentence that isn't ripe." His former traveling companion DuCamp founded a magazine, La Revue de Paris, and began to urge on him the idea of becoming established, of "making it." Literature, in DuCamp's view, was a product and one sells what the marketplace desires. Flaubert rejected this argument outright:

"It may well be that from a commercial point of view there are 'favorable moments,' a ready market for one kind of article or another. . . . Let those who wish to manufacture those things hasten to set up their factories: I well understand that they should. But if your work of art is good, if it is authentic, its echo will be heard, it will find its place -- in six months, six years, or after you're gone. What difference does it make?"

This faith in the ultimate recognition of good art is one that has consoled many writers since. Having been tested in these early years against the pulls of the both romanticism and expedience, Flaubert continued to defend disinterested, impersonal art throughout his career, in later years most vigorously against his friend George Sand's view that art should be socially useful and committed (see The George Sand-Gustave Flaubert Letters, Academy Chicago Limited, 5.95). Unfortunately, like many a founder of a sect, Flaubert also grew more intolerant and strident in later life: Soon after this volume of letters closes with the publication of Madame Bovary (1856) and its successful defense against charges of obscenity, Flaubert will begin to rage obsessively about his nausea for the bourgeois. His future books will be drier, more clinical, whether portraying the sensual carnage of Salammbo, the bitter ironies of L'education sentimentale, or the black humor of Bouvard et Pecuchet.

Nearly everyone agrees that Flaubert might have become an even greater novelist had he been less the rigorous writing machine and more a human being. Yet his fanatical devotion to exactness and form make him the best of all writing teachers, as Maupassant, Proust and Joyce all knew. "It takes more genius to say, in proper style: 'close the door,' or 'he wanted to sleep' than to give all the literature courses in the world." The Letters of Gustave Flaubert should both inspire and discourage writers of any age.