There is something odd about our cult of celebrity. Who is a "celebrity"? Are we really, as a society, "celebrating" all those newsreaders and cooks and keep-fit gurus who appear in huge spreads in Hello! and OK!? Of course, there's always been fame. But when I was young, famous people were really famous, like Burt Lancaster and Marilyn Monroe and the Queen. And they were in every part of our national life, like Roger Bannister and Edmund Hillary and Winston Churchill. Now, it seems to be all about media people, and media people of whom most of us have never heard.
All this has borne in on me lately because it seems I have become one of this ever-growing army. A couple of years ago, I exchanged the moderate profile of a character actor in a popular series for the role of yet another ubiquitous, opinionated "celeb". In March 2002, I won an Oscar for writing the script of Gosford Park, which triggered endless coverage on television and in the press, and now I have a novel, Snobs, to lay before the public.
Consequently, over the past few weeks, I have been back on the celebrity merry-go-round. The weekend before it was published, I had a long article in the Daily Mail talking about how I wooed my wife, then pages in the Sunday Telegraph recording my views on the contemporary upper classes. The following Monday, I was accorded "sex appeal" (for the first and only time in my professional life) by a columnist, and by the Friday I had been credited with criticising Anne Robinson, as well as enjoying a vast inheritance - both untrue, more's the pity.
What is slightly disturbing about all this is that, to the world at large, such treatment appears to confer on one a sense of knowing more than other people know. Strangers seek your advice endlessly because you are deemed to have "made it" and therefore must, in some way, be privy to the great secret of how it's done. Except you're not. Recently, as part of the Sell Snobs Campaign, I was giving a seminar at the PEN Book Fair with Anthony Minghella. He, I must say at once, spoke tremendous and valuable sense, but I felt rather a fraud: I never feel I know anything more about screenwriting than that one should try to write films one would like to see, and that one should stop if it's getting boring.
Success means your thoughts are worthy of everyone's consideration. Initially, this is heady stuff as you appear on Question Time or the morning news or Richard and Judy and mouth off about the state of society. The danger comes when you watch the programmes and see yourself blabbing away like a gobby fool. After that humbling experience, it is easy to be deflected into the modern fashion for being "non-judgemental". We have all seen those public figures who are so terrified of offending anyone that they simply spout anodyne views on anything from the Iraqi war to Munchausen's syndrome by proxy in a desperate attempt to upset nobody. I have now come to the conclusion that this is a mistake. If you're supposed to be a "personality", then you might as well have a personality. There isn't much point in the whole celebrity nonsense unless one is prepared to go out on a limb and, one hopes, speak up for some under-represented section of the community.
I was often asked, during the Oscar madness, whether or not I had anticipated the success of the film and the changes it would usher into my own life. The answer is no. I don't believe anyone making a film (or writing a book or painting a picture) thinks about anything other than getting the job finished. The "big picture" (to borrow a phrase from our celebrity-obsessed government) is completely concealed behind the daily difficulties of the task in hand. Even when I won the New York Film Critics Circle Award, I was still not aware of what it heralded. I was delighted and flattered but, as far as I knew, my life would continue in much the same manner as before. Professionally at least, I was completely wrong.
Now, I have published a novel. I would not have said that books seize the public imagination in quite the way that movies do, but even so I am engaged on my second odyssey to catch at the love of strangers. I have spoken on wireless programmes, done interviews for columnists and signings in bookshops. I suppose this is all designed to convince the world that I am an interesting person and that, therefore, by inference, my book will be interesting, too.
It is not exactly that I disagree with this approach. I truly believe the people from my publishers know what they're doing and I am sure it is the right way to sell a novel. But, even so, I cannot shake off the sense that, as a celebrity, I am a pretender. This is not false modesty. The book has spent the past five weeks in the bestseller lists and that seems to me to be something of which I may be justly proud, but I am still not convinced that my opinions are any more interesting than the views of the legendary man on the Clapham omnibus.
Perhaps that is the point. Perhaps by airing my frequently very ordinary ideas, I am giving the average man or woman, with their average worries and their average fears, a public voice. At any rate, I certainly hope so.
Snobs is published by Weidenfeld & Nicolson (£12.99)