It is, unbelievably, 50 years since the child care bible, Dr Benjamin Spock’s Baby and Child Care, was first printed. It remains one of the best-selling books of all time with more than 46 million copies in print. At 93, you’d have thought the doctor might have gracefully retired by now, but no, he’s working on the seventh revised edition due for publication in 1998.

With a vitality that belies his years, he works tirelessly from home with his second wife, Mary Morgan, 43 years his junior. He sticks rigidly to a macrobiotic diet, and is a firm believer in regular group therapy sessions. Rewriting his book, however, is now done with the help of a partner - fellow paediatrician Dr Michael Rothenberg.

For my mother’s generation bringing up children in the Fifties, Spock’s book was a godsend. It was the first practical self-help guide for mothers written in language they could understand, free from medical jargon, advocating that it was OK to feed your child on demand - and that four-hourly feeding patterns could be broken. This was revolutionary stuff in the 1940s - and led him much later to be charged with the responsibility for the permissive society!

Speaking from his home in the American state of Maine, his voice slightly cracked with age but still very positive in his views, he says he was the first to advocate a close, loving relationship between parents and babies.

“At the time my book was first written, paediatricians said you had to feed a baby on the dot of four hours - even if the baby woke up and cried you had to leave him until the feed was due. Most parents then felt they must be rigid and not indulge their children. I said you don’t have to be rigid and you don’t have to be afraid of being affectionate towards your children. I remember one American psychologist who actually said, ‘Don’t hug your child.’ Unbelievable! He also said, ‘Don’t pick your child up - but you can shake hands with your child first thing in the morning.”

The charge of creating the permissive society came at the time of the Vietnam war, which he violently opposed. “That was crazy,” he says. “Certainly I said be affectionate to your children - but I also advocated firm, clear leadership. I don’t think I’m responsible for those children who are out of control. ”

Spock had two children, Michael and John, from his first marriage. “I do have regrets - I don’t think I showed them enough physical affection. My own father didn’t show me that kind of affection and I think I followed his example. ”

But is his book relevant today? It has been consistently revised and updated; the latest has advice on how to talk to your child about Aids and drugs, and offers supportive advice for homosexual teenagers and their parents.

Virginia Burlton, a dentist living in Warwickshire, has a 13-month-old daughter, Laura. “I didn’t use Dr Spock’s book because I felt it was too old-fashioned. I much prefer to rely on a book written by a woman - somehow I feel she will have a better understanding of what I’m going through.

“I think new mums do still turn to self-help books - quite often now your own mother isn’t close and it’s so easy to panic.” She uses Miriam Stoppard’s New Baby Care Book.

Dr Stoppard - the first mother to write a self-help book on child care - says she relied on Dr Spock when she was bringing up her four sons. “He actually popularised the upbringing of children. Before then children had been very much seen and not heard.

“This was a hangover from the war in that children were really secondary. The important ones were the returning fighting men and the the women who’d stayed at home and worked. Children then were more like appendages and property.

“Spock brought about a quiet revolution in that he was the first to say that children were more important than adults. He said children had rights as individuals.”

But she says when she first turned to Dr Spock she was disappointed. “I expected him to lay down the rules, and I was thinking, ‘I don’t want this wishy-washy stuff’ - but then I realised he was saying it’s wrong to have strict guidelines for everything. After all, his first words in the book were, ‘Trust yourself; you know far more than you think you know’.”

Fellow childcare expert Penelope Leach, whose book Your Baby and Child is being rewritten, also acknowledges her own debt of gratitude.

“He was the first ‘expert’ who addressed himself to ordinary parents. What came before were patronisingly instructional texts.”

Today Spock is a firm advocate of family values - his latest book is called A Better World for Our Children; Rebuilding American Family Values. “There hasn’t been a breakdown in the majority of families but there is a significant minority who’ve lost conviction about how they should raise their children, ” he says.

“Children will take advantage if that conviction isn’t there. They are what their parents make them - violence in society and on television also plays a part.” He says in a society in which parents become mere chauffeurs and families rarely eat dinner together, children are being robbed of the stability essential to their development.

On a more cheerful note, however, he sees the role of the father as changing for the better. “They are playing a much more active role - not replacing the mother, but taking delight in the upbringing of their children.”

He enjoys the notoriety the book has given his life. “I get stopped in the streets and at airports by mothers who recognise me and say, ‘Thank you for helping me raise two fine children and I don’t see that your book is permissive!’ I say, ‘It was never meant to be!’.”

Diana Appleyard is the presenter of BBCRadio Four’s Education Matters, Monday at 11pm, Long Wave. Her interview with Dr Spock went out on October 21.