THE CHEAP SUBTITLE of this fine book, "The Godless Victorian," is unworthy of its author and its subject. In its earlier incarnation (1952) its title was discouragingly stodgy, but at least "Leslie Stephen: His Thought and Character in Relation to His Time" not only had an authentic Victorian ring but accurately described Noel Annan's intention, which was to blend straight biography with intellectual history.

A complex and inscrutable figure and a member of one of those first families of English intellectual aristocracy whose closely knit relationships through descent and intermarriage Annan once traced in a classic essay, Leslie Stephen was also a representative man -- representative, that is, of the troubled thinkers whose religious and moral opinions were formed by the powerful forces that eroded and undermined Victorian orthodoxy.

He was one of late Victorian England's busiest men of letters: the first editor of the monumental and still indispensable Dictionary of National Biography, to which he contributed no fewer than 378 long articles on English writers, and the author of separate biographies of Pope, Swift, Hobbes, and Dr. Johnson, and of a two-volume History of English Thought in the Eighteenth Century, which remains a standard work after the passage of more than one hundred years. His lectures on English Literature and Society in the Eighteenth Century were among the earliest exercises in the sociological study of literature. After Matthew Arnold, he was the most considerable critic of his time and the first to regard fiction as a serious form of literary art.

Stephen was nothing if not versatile. With one pen he could turn out a weighty history of English Utilitarianism, not the most sparkling of topics, and with the other, engaging essays such as his witty discourse on "The Decay of Murder" (1869), which anticipated George Orwell on the same mock- lugubrious theme by 77 years.

In some ways, like most of his fellow doubters, Stephen was the epitome of conventionality. As editor of the Cornhill Magazine, where he published early work by Henry James and Robert Louis Stevenson, he bowdlerized Hardy's fiction, his apologies to the offended author not wholly concealing the fact that the squeamishness he attributed to the magazine's readers was also his own. His anti-feminism followed the line adopted by all but a tiny handful of his contemporaries. On the other hand, on some social issues he was unfashionably liberal.

His greatest dissidence was in religious mattters. Raised in a family belonging to London's well-to-do Clapham Sect, of which the Macaulays and the Wilberforces were also members, he encountered doubt atambridge, where his studies led him to cast loose from the Evangelicalism they so fervently espoused, then from the doctrines of the Anglican Church, and finally from Christianity altogether. As a consequence he resigned his tutorship at the university and renounced Holy Orders. Deprived of both an academic and a clerical livelihood, he had to make himself a career in literary journalism and editing. Fortunately, the late Victorian literary marketplace not only tolerated but rewarded gifted writers with something to say, even if it was provocative, and Stephen prospered and eventually received a knighthood, chiefly for his work on the DNB.

HIS HETERODOX opinions apart, Stephen was a man of contradictions and crotchets. There was a definite strain of mental instability in his family, which he may subconsciously have striven to exorcise by strenuous physical activity. He rowed at Cambridge and became a first-class coach, and in his middle years he was a tireless walker; he was the guiding spirit of a Sunday walking club composed of scholars and journalists who routinely covered 20 miles a day, and on his own he often did 40. Most surprisingly, he was a pioneer Alpinist and an eloquent writer on the esthetic, mystic joys of mountain climbing.

Stephen was at once a self-tormentor and a humorist, an apostle of reason -- his intellectual sympathies were deeply rooted in the Age of the Enlightenment -- and a victim of black moods and unmastered emotions. He enjoyed lasting friendships, and among his intimate correspondents were those bastions of the Boston literary establishment, Charles Eliot Norton, James Russell Lowell, and Oliver Wendell Holmes. Yet in social relationships he was unpredictable and often distressingly difficult. In his last years, after his second wife's death (his first was Thackeray's younger daughter), he became more and more a recluse. As a family man he alternated between warm affection and chilling distance.

Ironically, it is in his role of pater familias, with distinct overtones of King Lear, that Leslie Stephen is best known today, although the effect of Annan's book when first published was to stimulate renewed interest in him as a critic and historian of ideas. He was, as everybody knows, Virginia Woolf's father, the partial model for Mr. Ramsay in To the Lighthouse -- a gloomy and selfish man who adamantly opposed his daughters' seeking education outside the home, a presence whose tyranny clouded Virginia's childhood and adolescence.

To understand her, one must first understand her father. The modern rage to know everything possibly discoverable about Bloomsbury and Virginia Woolf in particular has brought to light a wealth of personal information not available to her father's biographer 30 years ago. It was this windfall (Lord Annan, as he now is, generously credits numerous American scholars' contribution to it) that, in addition to a wish to probe more deeply into the German antecedents of Stephen's thought, encouraged him to substantially rewrite and enlarge his earlier book. The result is an altogether better informed and wiser study of a man who, in the best of circumstances, resists full explanation.

Assuredly, Leslie Stephen would not appreciate the fact that his wider fame is now contingent on, and subsidiary to, the much greater celebrity of the daughter he failed utterly to understand. But as a student and practitioner of the difficult art of biography and a historian who knew how crucial the impact of ideas on character can be, he would applaud Annan's book, one of the best biographies we possess of any eminent Victorian, devout or agnostic.