Dr Benjamin Spock's Common Sense Book of Baby and Child Care is one of the best-selling books of all time, with overall sales of some 50 million. Sixty-five years since its first publication, what is Dr Spock's contribution to child-rearing today?
The book's title wasn't the most exciting. But in the austere post-war years its message was revolutionary.
"As soon as it hit the market, it was acclaimed," says Professor Lynn Bloom, Dr Benjamin Spock's biographer and friend.
"It was so radical and so different from the child-rearing manuals that preceded it.
"People wanted the opportunity and the sanction to have children and to love them. And that book did this."
Baby and Child Care challenged the child-rearing orthodoxy of the early 20th Century - that babies should be fed according to a tight schedule, and that showing them too much affection made them weak and unprepared for the world.
Instead, Dr Spock encouraged a more gentle approach to bringing up children, and told parents to trust their own instincts and common sense.
"I urged parents not to be intimidated by the rule that had existed in paediatrics up until that time - you must never feed a baby off schedule, not a minute early, not a minute late," he said.
"I was one of the first paediatricians to say that's nonsense. That rule made babies cry.
"It was even harder on mothers, they bit their nails in anguish waiting for the clock to say this is the minute you can feed."
The opening sentences of the book are: "Trust yourself. You know more than you think you do."
In 1946, that was a big departure from the prevailing wisdom, that doctors and paediatricians knew best.
In the first six months after it was published, Baby and Child Care sold 500,000 copies.
Within a decade that had risen to a million a year. It has now been translated into 39 languages, with sales estimated at 50 million.
By the 1960s, when Lynn Bloom first met Dr Spock, Baby and Child Care had already become one of the best-selling non-fiction books of all time - and every new mother she knew had a copy.
"It was at the time the only book in town.
"There were some other specialised books on natural childbirth, there were books on breastfeeding, but this was the only game in town, and it was one that people didn't question.
"The subtitle of the book was the Common Sense Book of Baby and Child Care. So if you had half a grain of sense you knew that the advice would be compatible with your own best instincts."
Lynn Bloom remembers Benjamin Spock as someone who loved children, who would get down on the floor to play with them - a big man, more than six feet tall, with a booming laugh. And a very humane man.
"I never heard him in private or in public utter any comment that was in any way denigrating, demeaning, that pulled rank, that indicated that he thought he was grandiose. I don't think he felt that way."
Benjamin Spock was born in 1903 - the eldest son in a family of five children, who would often look after his younger siblings.
His mother's own style of parenting was fairly harsh.
"One of her punishments was to put children in a dark closet and to simply leave them there until they learnt whatever lesson she was trying to teach them.
"Two of Spock's sisters each remember that she put them in a closet and forgot about them, and went off to New York for the day, came back and they were out of their minds practically, with apprehension.
"It sounds severe. It was severe. But it wasn't unusual for that time in which Spock was raised."
Benjamin Spock went to Yale University - where he joined the rowing crew that won a gold medal at the Paris Olympics in 1924 - and studied medicine specialising in paediatrics.
In later life, he developed another passion - politics.
In 1960, he made an advertisement with Jacqueline Kennedy as part of John F Kennedy's presidential election campaign.
He joined the peace movement and by the late 60s was a leading activist in the anti-Vietnam war movement.
Explaining why he became more political, he said: "It isn't enough to bring up children happy and secure, you need to provide a decent world for them. And this is why I have expanded my horizon."
In 1968, Dr Spock was given a two-year jail sentence, which he never served, for aiding resistance to the draft.
He also received death threats and his book was attacked by the war's supporters, who blamed his liberal advice to parents for breeding a permissive, self-indulgent generation.
It was a charge Benjamin Spock tackled head-on in a BBC phone-in in 1971.
"I am accused by certain political types like the Vice-President Spiro Agnew, he's been going over all the US saying that the young people are ruined because I gave permissive advice," he said.
"Actually, I think anyone who has read Baby and Child Care understands that I am not a permissivist, that I never talked about instant gratification."
But the damage was done. Dr Spock would never quite shake off that reputation among the conservatives as a corruptor of the young.
Some of his advice was later discredited medically - for example, the idea of putting babies to sleep on their stomachs. He said it reduced the risk of infants choking on their own vomit, but by the 1990s, the practice was being linked to sudden infant death syndrome.
Sixty-five years on, however, Dr Spock's Baby and Child Care is still in print - and it continues to influence generations of parents.