Affairs between people whose ages differ by many years "is the basis of civilization," believes Stephen Vizinczey, author of a 1965 best-selling novel, "In Praise of Older Women."

That's true, he says, whether it's the older man and the younger woman or vice versa. But only for the short term: "Not for marriages, or long-run things."

It is, at least, controversial advice that is not going to win him friends among many parents.

Still, he says, for young people, it is a "growing" experience. "I have a young daughter. If she would in time have an affair with an older man, I would be happy -- but very unhappy to see her marry one.

"I am against young marriage. I don't believe young people can go together. Too many immature people get married.

"A good age to marry is when they know who they are -- around 30. I got married at 30 and I'm happily married for life. At 20, it wouldn't have worked. I got married at 20, and it didn't."

Hungarian by birth, Vizinczey, 47, lives in Toronto. His novel of erotic experience -- which, he says, is partially autobiographical -- was written when he was 30. One reviewer called it "a valentine" to older women. A new edition recently was put out in Canada and elsewhere, but not in this country.

For the older half of any couple, the relationship brings "a freshness in life." Older people who stick with their own age group, he says, "have a tendency to grow old."

If they're with a younger person, they are likely to do things "they've gotten out of the habit of doing -- taking a walk or riding a bus. It's good for you."

And, "They rediscover their youth. Youth and age can give everything to each other."