I used to get irritated by Jack Nicholson. I got tired of seeing his perennial Oscar nominations, his "I'm so cool" shades, his keenness to expose his endless sexual conquests and general hedonism.

I would never have denied he was a good actor, of course. Indeed One Flew Over the Cuckoo's Nest, Five Easy Pieces and Terms of Endearment are among my favourite films. But the Nicholson persona irritated me. Maybe it's partly because in the movies he likes to cultivate the image of being a rebel when, in reality, he's clearly part of the A-list Hollywood establishment.

Every August Nicholson seems to crop up in the South of France, surrounded by a bevvy of beauties young enough to be his granddaughters. He's always smoking and partying and generally having a good time. And let's face it, the South of France is still the epitome of cool. And every year the British press takes photos of his ever-expanding girth sinking into the Mediterranean waters.

A few years ago I read an interview with Nicholson in which he said something that really made me think. If you think I'm alluding to some breathtaking political insight about the nature of capitalism or the Iraq war or global warming, go elsewhere - to a Vanessa Redgrave or Sean Penn or Jane Fonda perhaps. No, this was - on the face of it at least - something far more mundane. In this interview Nicholson said: "I teach my kids not to feel guilty about having a good time."

Wow! I was about 35 at the time but that had never crossed my mind. I came from a middle class British background. My father was a liberal-minded Jewish man with an ingrained sense of pessimism, probably a legacy of the Holocaust. Although we had good times we could never enjoy a great meal, for example, without my father reflecting on global starvation and how lucky we were to be eating so well. Just when I was enjoying the sublime taste of that avocado and prawns my father would hit me with the plight of famine in Ethiopia. Prawns served on a plate with a heavy dose of guilt. Fun always came with a grim health warning and a sober assessment of a potential global apocalypse.

My mother was a bit more fun-loving but if I'd told her that the previous night I'd enjoyed a few beers and a curry and God forbid - female company - she would have ummed in just such as way as to instil a vestige of guilt and self-reproach. Then a seven second pause before she would say "I see".  

Hence Nicholson's words were a real eye-opener for me. As I 've got older I'm starting to realise the importance of fun in people's lives. Nicholson himself always seems to know how to enjoy himself, whether it's holidaying in the sun, dancing at nightclubs or attending his beloved Los Angeles Lakers' games.

Of course, few of us can have fun at Nicholson's level. After all, he's worth 140 million pounds. But when the opportunity arises we should enjoy the best of times without guilt. After all, forsaking a fun-filled holiday will do nothing to alleviate global famine.