The sage in the aquarium

Because he lived so long we tend to think of Bertrand Russell as a very old man. Many of us grew up with the image of the ancient sage squatting defiantly in Trafalgar Square. He died in 1970, aged 97, an almost disembodied spectral intelligence stranded from another age. To his dying day he railed against nuclear weapons and the Vietnam war. But longevity lends a sort of sainthood even to the most determined subversive, and he died loaded with honours from a Nobel Prize for Literature to the Order of Merit.

More than half a century earlier he had been hounded from Cambridge for opposing the First World War and imprisoned for insulting the Americans. (Consistency was not always Russell's hallmark but in this respect it was impressive). And even then he was in his forties. This first volume of Ray Monk's new biography covers only the first half of Russell's life, ending in 1921 with his second marriage (two more still to come) and the birth of his first child. But already the scale of it is stupendous.

Russell was one of those people who wrote almost continuously; he lived his life on paper. His published writings - on philosophy, politics and social organisation - are nothing beside his letters, some 60,000 of them, mostly intimately autobiographical, plus journals and a number of attempts at thinly disguised fiction. Monk compares him to Virginia Woolf; but the only comparable logomaniac over such a lifespan is Shaw - with the difference that Shaw's verbosity was poured outward upon the world, whereas Russell's private writings are all about himself.

The raw material for biography here is unequalled and almost overwhelming. If it can ever be possible to reconstruct from day to day the mind of another human being, Russell has left his biographer that opportunity. Hitherto Monk's predecessors - most recently Ronald Clark in 1975 and Caroline Moorehead in 1992 - have barely scratched the surface. Ray Monk has dug deep and - quite rightly - quotes extensively. The result is frequently appalling: Russell's self-righteousness is repellent, his self- loathing painful, his self-deception comic. His utter self-absorption is staggering but ultimately, Monk persuades us, tragic. He sought love with a bewildering catalogue of women, he tried desperately to love humanity. But he always felt alone. He once likened himself to a fish in an aquarium, trying to make contact but unable to communicate. All he could ever see in the glass was his own reflection.

Ray Monk is qualified as no previous biographer of Russell has been by the fact that he understands the philosophy. His biography of Wittgenstein was highly praised for humanising that most intractable genius; and one of the most poignant strands of this book is his account of the Russell- Wittgenstein relationship, in which their original roles of teacher and pupil were reversed to the point where Wittgenstein, in 1913, torpedoed the whole basis of Russell's logical system. Non-specialist readers will find Monk's exposition of Russell's mathematical philosophy difficult, if not meaningless. But Monk understands it and, more important, he is able to convey both the sense of struggle at the very limits of the intellect and the importance to Russell of his quasi-religious search for ultimate truths through mathematics, so that we can feel the devastating impact of the discovery that Wittgenstein - far from building on his work, as he had imagined - had demolished it.

Russell was repeatedly let down by those who he persuaded himself shared his deepest beliefs. It was the story of his intellectual life; he suffered another devastating rejection in 1915 at the hands of DH Lawrence, whose mystical instinct- worship he briefly embraced in a deluded attempt to escape from barren intellectualism. Still more it was the story of his love life.

Obsessed with sex, and as desperate to lose his virginity as the most pimply adolescent, he first contracted the most inappropriate possible marriage to a strait-laced American Quaker, Alys Pearsall Smith, under the fantastic illusion that she was an apostle of free love. Having realised his mistake, he subjected her to nine years of callous and priggish cruelty before abandoning her for Ottoline Morrell, whom he almost as hopelessly misjudged. Ottoline loved him in her way - though found him physically repellent - but she also loved a lot of other people, including her husband, whom she refused to leave. (Compulsively unfaithful himself, Russell was nevertheless furiously intolerant of any hint of infidelity in his women). Their bizarre affair lasted six years, during which he broke the heart of at least one other - another American, Helen Dudley, whom he persuaded to come to England to marry him and then rejected the moment she arrived - and toyed fatally with the affections of another, Vivien Eliot. On Monk's account Russell was as responsible as her husband for Vivien's breakdown and committal to an asylum, from which she never emerged; and the evidence is that he knew it.

Then there was Constance Malleson (the actress Colette O'Neil), another married woman for whom he conceived a mismatched passion: she refused to give up her profession and refused him children, which was what he now wanted more than anything. Dora Black, a free-thinking New Woman straight out of HG Wells, was incompatible in several other ways, but she was willing to bear his children, though preferably without being married. Comically the great radical was concerned that the heir to the Russell earldom (his elder brother had no sons) should be legitimate; so against her principles and five months pregnant, Dora became his second wife.

Does this serial bed-hopping sound contemptible or absurd? It is a measure of Monk's achievement that it does not read so. Through the medium of his letters to all these different women (and theirs to him) he manages to make Russell's quest for his ideal woman part of his wider intellectual odyssey. What he always wanted was a woman who would share and help him in his work, which was just what all the women he was attracted to would not do. He was torn all his life between intellect and emotion. He was passionate in his philosophy, but cripplingly cerebral in his analysis of his emotions. It was during his years of miserable celibacy with Alys that he did his hardest mathematical work. In pursuit of sexual fulfilment with Ottoline (and after Wittgenstein's blow to his intellectual confidence) he abandoned abstract philosophy and sought to engage with the real world. But nothing satisfied his demon.

In the end, for all his desire to believe in something, scepticism kept breaking through. In 1920, like other credulous Western intellectuals, he went to Russia to inspect the new Soviet utopia. Where Shaw and the Webbs saw a higher civilisation, however, Russell saw only tyranny. The experience of Russian Communism, he wrote pathetically, only proved that "kindliness and tolerance are worth all the creeds in the world".

A more homespun philosopher reached the same conclusion the year before Russell died: "All you need is love." But poor old Bertie never found it.