In his poem "Ignorance of Death" William Empson remarks that death is "the trigger of the literary man's biggest gun"; but reminds us that we have no experience of death - of our own, that is. "Otherwise I feel very blank upon this topic, / And think that though important, and proper for anyone to bring up, / It is one that most people should be prepared to be blank upon." And as Wittgenstein informed us in the Tractatus, "death is not an event in life".

That doesn't stop us from being terrified of death, not being nearly as blank as we should be on the subject. Here Julian Barnes, in a witty, engaging, rambling disquisition on the subject, addresses his own and others' engagement with the end that awaits us all. This could be said to be an eschatological book, in that he considers the Four Last Things - death, judgement, heaven and hell - but without, because of his atheism, worrying too much about the last three. But there is a certain amount of theological throat-clearing, as you should expect.

After a while - a very short while, in fact - it becomes clear that this is also a kind of engagingly hazy autobiography, as Barnes spends at least as much time delving into his family history as he does musing about death. This is perhaps just as well: doing too much of that can drive you mad. Look at Larkin's "The Old Fools": the poem's motor runs on terror ("Why aren't they screaming?"). And as Barnes mentions here, when Larkin was on his deathbed, he would have been raving had he not been sedated. (You may find that the most effective technique in this book for avoiding the fear of death is that employed by Turgenev: "he would brush it away like this - and he demonstrated a little gesture of the hand. Russians, he said, knew how to make things disappear into a 'Slav mist', which they summoned up to protect themselves from logical yet unpleasant trains of thought.")

But the star of this book is the author's brother: three years older than Barnes, and such an archetypal big brother that he is almost incredible. A philosopher, and therefore one with strict habits of thought and speech, he regards many of young Julian's utterances as intellectually woolly or even - when asked to contemplate the book's opening statement ("I don't believe in God, but I miss Him") - "soppy". His occasionally chilling advice or logically perfect pronouncements obviously exasperate Barnes, but they light up the book. He visits the hospital and turns down a free blood test for what turn out to be very sound reasons, baffling a persistent nurse, "clearly not knowing what manner of patient she had in front of her."

If there is an antihero in the book, it is their mother. It is rare, if not as rare as it used to be, to read such invective; not that Barnes rants and raves - it becomes gradually clear that he barely approves of her at all, regarding his father's silence as no more than the result of having been steamrollered by an endless stream of unpleasant banalities. Once, Barnes hid a tape-recorder under the dining-room table so that he could play back their phatic conversations to justify his bringing down a book to read; to his dismay, his mother was delighted by the tape, comparing it to a Pinter play - "to my mind a mixed compliment, in both directions."

But this is, on the whole, a philosophical work - the business of philosophy, as Montaigne and others have reminded us, being to teach us how to die. Hence the importance of his brother. But it is also a meditation on writing, on literary posterity, on the characters and equipment of writers ("The only, single difference between them and other people, the only, single way in which they were better, was that they were better writers"). Barnes, francophile that he is, gives us plenty of Montaigne, Renard, the Goncourts, Stendhal; yet there is more than surface urbanity here, and when he quotes, he quotes well. (Even his GP gets a few well-chosen words in.) It's the kind of book, I imagine, you wouldn't mind having by you if you were on the way out.

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