HENRY JAMES: A Life. By Leon Edel. Harper & Row. 768 pp. $24.95.

IN 1914, TWO YEARS before he died, Henry James declared war on prospective biographers: "My sole wish," wrote the novelist to his literary executor, "is to frustrate as utterly as possible the post mortem exploiter." He burned manuscripts and letters, considered including in his will "a curse no less explicit than Shakespeare's own on any such as try to move my bones," and proclaimed his "utter and absolute abhorrence of any attempted biography or the giving to the world . . . of my private correspondence."

Leon Edel, whose outstanding life of Henry James was published in five volumes between 1953 and 1972, and who has been giving the world James' finely edited private correspondence since 1974, may often have shuddered under his subject's absolute abhorrence of these endeavors. Yet the author of The Aspern Papers made an allowance: when biography illuminates the process of artistic development, he wrote, when it is a "quest of imaginative experience," then it can be "one of the greatest observed adventures of mankind." And he nodded approvingly at the search, in Sainte- Beuve's biographical studies, for "the seam as it were between the talent and the soul." Although Edel no doubt looked more closely into private questions than the fiercely reticent James might have liked, he has with this monumental work helped turn modern biography toward the quest of imaginative experience, and has throughout traced the seam (minus the Jamesian "as it were") between talent and soul.

With the help of his English editor, Catharine Carver, he has now cut the five volumes down into one. It is a remarkable job of condensation and revision: read alongside the original, the "new" story seems less roomy, with somewhat less luxuriant detail, shorter quotes, briefer accounts of various family members, literary acquaintances, and friends, and only one illustrative incident where there had been two or three -- but it still has the powerful grip of the larger narrative. And he has made useful changes (I'll come back to these in a minute) without significantly altering the famous features of his full-length portrait.

Asked by a friend about the port from which his life had originally set sail, James, in his sixties, replied: "The port from which I set out was, I think, that of the essential loneliness of my life . . . what is it still but the deepest thing about one? Deeper, about me, at any rate, than anything else; deeper than my 'genius,' deeper than my 'discipline,' deeper than my pride, deeper, above all, than the deep counterminings of art." For Henry James, nothing else ever went as deep as his genius or his art, and perhaps the more searching treatment of love in his late novels has to do with this fundamental solitude: it was too late for him to take the advice Lambert Strether gives to Little Bilham in The Ambassadors -- "Live all you can."

He had had, from very early on, both a sense of isolation and an absolute faith in his own talent. As a boy, he was the shy, in-dwelling little "Harry" whose energetic elder brother, William, seemed always ahead somehow, "round the corner and out of sight." Explaining why Henry couldn't tag along after him one day, William announced loftily, "I play with boys who curse and swear!" The second son quickly became the good child in the family drama, his mother's "angel," a voracious receptor who chose to watch rather than act, to absorb the rarified "sensuous education" offered by his father in books, art, theater and European travel. But if the young esthete ducked out of the competitive masculine fray, he was anything but timid about his literary career. He counted up the frst 12 dollar bills he earned with his pen (for a critical piece in the North American Review) when he was 21. By 35 he had moved to London, taken as his models Balzac, Thackeray, George Eliot and Turgenev, published widely on art, literature and travel, and established himself as a transatlantic novelist with Daisy Miller, The American, and The Europeans on his shelf and The Portrait of a Lady soon to come. He kept on writing, virtually without interruption, for the rest of his life, and referred again and again to his "genius" as if it were his greatest ally and invariably trustworthy friend. At 66, struggling against depression, he sat down to write a story and thanked the "celestial, soothing, sanctifying process, with all the high sane forces of the sacred time, fighting through it, on my side."

By contrast, what he called "the great relation" -- between men and women -- seemed anything but sacred, sane, or safe. He had intimate female friends (including Edith Wharton, Fanny Kemble, Constance Fenimore Woolson) and was no prude: wandering one day with Mrs. Wharton through George Sand's country house, Nohant, James wondered aloud in which room the adventurous French novelist had slept -- then, archly, ''Though in which, indeed, in which indeed, my dear, did she not?" Yet he appears never to have had a sexual interest in women. Most of his female companions were safely married or too old (he once noted that the combined ages of his three favorite women came to 250), and he signed a letter to William, denying rumors of his impending marriage in 1904, ''always your hopelessly celibate even though sexagenarian Henry." The one woman who may have expected more than friendship from him, Miss Woolson, killed herself in 1895, leaving James immeasurably mystified and sad.

THE "sexagenarian Henry" did fall in love, however, with attractive younger men, and some of Leon Edel's changes in the abridged text have to do with these amorous (but probably not explicitly sexual) friendships, and with just what James knew of sexuality and love. Revising in the 1980s, Edel could take advantage of the more "unbuttoned ways of our age" (he writes in a preface), and discard some of the reticences and "proprieties" he had felt constrained by when he began in the 1950s. He speaks more openly now about the homoerotic undercurrents in Victorian society, as well as about the nature of James' celibacy and the profound feelings evoked in the aging artist by the handsome young sculptor Hendrik Anderson, the writer Hugh Walpole, and that elegant specimen of Anglo-Irish gentry, Dudley Jocelyn Persse. This access of love came too late to change James' pattern of life, but nothing was too late for the writer who claimed, through one of his characters, ''When there's anything to feel I try to be there." For all his "essential loneliness," James wrote about the intricate complexities of human relations with perhaps greater acuity than anyone has brought to the novel before or since.

The revisions here consist of careful rephrasings rather than sudden revelations about the novelist's private life, and if I have one small objection, it is to the occasional introduction of words such as ''gay" and "libidinal," which seem out of keeping with the rest. More important than any radical unbuttoning is a subtly altered reading of Henry's relations with his brother, William, which some critics have accused the novelist's biographer of casting too much in the light of rivalry and competition. In response, Edel now discusses the unusual fraternal ''twinship" from which each brother struggled to differentiate himself -- without discarding his earlier (and I think also quite correct) view of a primal Jacob/Esau struggle that was at once loving and antagonistic. Edel further amends his text to incorporate information from books published after his own volumes appeared -- incluing Howard Feinstein's Becoming William James, R.W.B. Lewis' Edith Wharton, and my own Alice James. For the most part, his earlier readings of the novels and tales stand (though on shorter legs), but he has found a definitive new source for the famous ghost story, The Turn of the Screw, and he now places Isabel Archer, in his chapter on The Portrait of a Lady, against a different backdrop -- the ideas of American Transcendentalism -- than he did in the earlier version.

The picture of Henry James that seems to have lodged in the public mind's eye is of the aging Master with his Anglophilic tastes, generous girth and prolix style. One lady bragged, when the expatriate author toured America in 1905, that she could read Henry James "in the original." Some years later, Faulkner inimitably called James "the nicest old lady I ever met." The elaborate indirections of the late style can be difficult, but it is impossible to read Leon Edel, in the long or short form, and not see the dignity, humor, and large compassion in James' final years, and behind them the shaping of an extraordinary talent and soul.