Australians, in my experience, however deeply transplanted, still crave the cerulean skies and bright light of their birthplace ­ which is why it is unexpected to find Clive James, on the sunniest of English spring mornings, in a curtain-drawn lair of such impenetrable gloom that the atmosphere seems to fizz with electricity from all the wattage. Or, perhaps, that's just the effect of his personality.

His London pad is in a converted warehouse near Tower Bridge. It's wine-bar territory rather than the sort of coffee-house bohemia that is his preferred habitat but that's precisely why James chose it ­ all the easier for him to guard his anonymity and get on with the serious business of writing and, ah, tango dancing.

Most of the walls are covered with thousands of books: old Penguin novels with their classic orange and white design, and titles covering every subject that could conceivably prick the curiosity of their owner's magpie mind. (This is a man who, after all, has painstakingly acquired at least six languages, including German, French, Spanish, Italian, Russian and Japanese, in order to read certain books in the original.) There are also paintings by his artist daughter, Claerwen, many photographs of beautiful women, including his wife, various objects from his travels and "Postcard from..." television programmes, and a loo full of Schiele-like nudes.

We sit at a dining-room table in the hall on high-backed Mackintosh chairs (only repro, James assures me) and get stuck in. His new book, Cultural Amnesia, is an 800-page whopper, which has taken him four years to write and all his life to collate. The subtitle is Notes in the Margin of My Time, and although there are many different figures in it, both well-known and obscure, the one that weaves through them all is the author himself.

This is Culture with both a large and a small C as befits the man who dubbed himself a premature post-modernist: "Hard to say, isn't it?" he says, "Crazy name! Crazy guy!" ­ so under M, you will find Thomas Death in Venice, The Magic Mountain Mann, preceded by Michael Miami Vice, Manhunter Mann, sandwiched by Norman Mailer and Mao Zedong. American talk-show host Dick Cavett, Coco Chanel and Tony Curtis are given equal billing to Cocteau, Camus and Chesterton.

Several times in our interview ­ when we talk about lust, for instance, or sensitivity to criticism (neither of them foreign to James) ­ he directs me to one or other essay in his book. Ernesto Sábato, an Argentinian writer ­ "take this down", James dictates, spelling out his name ­ is quoted: "Only a thick skin can defend itself, and the characteristic of an artist is an extreme delicacy of skin", which prompts our cultural guide to ponder how the statement might apply to himself ­ "If I had my time again, I would never react publicly to criticism, no matter how unjustified."

A page or two on, and he's into the tango ­ "a sad thought, dancing" (coined, not by Sábato ­ we learn ­ but by a vernacular poet, Enrique Santos Discépolo, in the Thirties; the book is full of such snippets of what James is proud to call useless knowledge) ­ and he's off again: "Undoubtedly it was the sight of old goats with pretty young women in their arms that helped draw me into the tango world, a man in winter longing for a touch of spring", and on through a dazzling and sometimes beautiful series of seemingly unconnected connections ­ like a jazz riff, the notes scattering and cohering ­ to his conclusion: "A man who wants to find out who he really is should try watching the woman he loves as she dances the tango with a maestro." There is more along the lines of this Old Man Winter refrain, prompted only partially by my first question. In the introduction to the book, James suggests that such a colossal work ­ based on four decades of jottings and notes ­ was something he had planned to write towards the end of his life.

So is the publication of Cultural Amnesia accompanied by the sound of a bell ominously tolling? "I've been feeling towards the end of my life-ish since I was about 24," he wheezes and laughs. "I used to have some very bad habits including drinking, and I thought I'll never last at this rate, especially at the rate I smoked. I always feel like I'm living on borrowed time... So I do feel this is the last round-up," his voice taking on that ironic Jamesian swoop, "but as my friend P. J. O'Rourke has already warned me, I can overdo this last-ditch stuff. You can't spend 20 years saying this is the last gasp."

But you're not really all that old, are you? "No, I'm a fairly young 67," he says, a little smugly. "I'm just wearing the internal effects of having smoked since I was nine." He tosses aside the suggestion that this sounds as though he's hinting at something sinister: "I've got the lungs that anyone would have who's smoked since that age." And then: "I'm not sick. I haven't got time to be sick... I've no time to die." He goes on to introduce his comments, several times, with the portentous words: "If I am granted life..." which seems to intimate a certain preoccupation with his own mortality.

England has been his home since James arrived here aged 21, but he has always been bewildered by the prevailing attitude that there is something suspect about throwing yourself into learning for learning's sake; that it is bad form to wear your erudition as unlightly as he has been known to do.

In the old days, some of this hostility may have been attributed to a strain of anti-Australian snobbery, what James considers was "a licensed anti-semitism, particularly among the Private Eye crowd." But there are plenty of towering English talents ­ Peter Brook and the late Anthony Burgess, to name two ­ who have also despaired of their own country's anti-intellectualism.

Cultural Amnesia is aimed at the clever young ­ perhaps, like his whizbang, multimedia website, of which James is inordinately proud, it is another bid at longevity. "The hardest thing when you're a young person going into university or the world is to figure out how it all ties up; the answer is that it doesn't, and it takes a lifetime to find out why. It's always handy to have voices somewhere up ahead of you, which I always did, and they tend to be the writers we worship ­ in my case, people like Scott Fitzgerald and Camus. Camus is one of my her-ow-ww-ws," James says dragging out the vowels, like a dog howling at the moon. "And I wanted to write a book that would do that job for the next generation."

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