William Empson, volume 2: Against the Christians, by John Haffenden

The story so far: in the first volume of John Haffenden's biography, William Empson was born in 1906, became a dazzling scholar and poet at Cambridge, was sent down for possessing contraceptives, drank his way around literary London, published two subject-changing books, taught in China after the Japanese invasion and got out with Boys' Own Paper adventures, returning home in 1939 after having stopped off in Los Angeles to go to a park and have a good scream.

Empson joined the BBC in the overseas service, where naturally he acted as Chinese Editor and, working alongside George Orwell, made cultural propaganda of an unvarnished kind, in any case expressive of his fiercely honest and generous nature. In 1941 he married Hetta, a beautiful Boer and ardently Communist sculptor, Empson's wife for 43 years and mistress to uncounted applicants, some procured by her always complaisant husband. In 1947, accompanied by two sons, the family went to Peking where Empson taught as dedicatedly as he and his wife drank gut-rot Chinese wine and "voddy", and where in 1948 the city was besieged by the Communists. He stayed on as the People's Republic was inaugurated, until 1952 when, after the Korean Settlement, the Americans more or less forbade anybody to talk to the Chinese.

Haffenden, as always, is scrupulously detailed in showing how Empson, a gentlemanly English Leftist, greeted the revolution in a characteristically open-hearted, innocent way. He defended it and its victims, and when later he made up a few of the large holes in his income by teaching in the US, he was at pains "to give a good political scolding" to America about China.

Often mumbling and inaudible in his lectures, speaking a Wykhamist-and-clubland argot, sudden and swooping in his exhilarating curves of thought, frequently tight in public, he nonetheless captivated the students. After assuming for 18 years the Chair of English at Sheffield, he won from his colleagues absolute esteem, slightly fearful loyalty, and a proper deference towards his achievements.

Haffenden is splendid on these latter, threading them along Empson's monomaniac theme of anti-Christianity. That magnificent book, The Structure of Complex Words, pre-empted the argument of J L Austin's revolution in linguistic philosophy, but time and again the force of the exemplary words - fool, dog, rogue, honest, wit, sense offer an unnerving sample - is also analysed to discover mischievous meanings, subversive alike of Church and State.

In a wonderful essay on John Donne, he rebuts those pedants who would make Donne a mere virtuoso of figures of speech, and finds his greatness in the way his poetry so vividly dramatises the balance of tense oppositions between belief and feeling. Hence Empson's assault on God in Milton's God, where with such daring and percipience he proves Blake right: that "Milton was of the devil's party without knowing it".

It was a lifelong campaign, and it matched his mind to his morality. For his innocence and his tolerance of human oddity were revolted by the primitive heart of Christianity and its hideous emblem. Those same virtues extended far beyond most people's limits to the way he permitted Hetta all her lovers, to the extent of seeing her off to join one in Hong Kong, and welcoming her back plus another son not his own. Order, for Empson, reposed in the art of his own verse, and ease in the regardless squalor and consistent devotion of domestic life; both expressions of an unshaken, unsharable ethics.

Throughout his mammoth work, Haffenden keeps up his equable manner, describing with the same calm raging quarrels at drunken parties and the subtle turns of readings of Coleridge. Yet to register Empson's weirdness of character, a touch of hysterical laughter is surely called for. There was, for a start, the grotesquerie of his beard, a star-shaped fan below his chin, or his demure request to a young colleague that he be allowed to kiss his member, or a typical menu for guests in "the Burrow", his filthy basement flat: hard-boiled egg in bottled curry sauce followed by a doughnut soused in condensed milk, plus a tumbler of Japanese whisky.

Biography is a dominant form these days, and Haffenden's is one of the best. A story in a history is probably the best way we have for grasping a corner of the globe. Yet this mighty work somehow fails to place its extraordinary subject against the moral horizon which would give him meaning. Haffenden, omniscient and stylish, is yet like a sculptor who, failing to find the shape within the stone, can only deliver a mountain of chippings, and leave them to fall into their own pattern.

Fred Inglis is writing the life of RG Collingwood