London — Can the family be strengthened by less state help instead of more? ''No,'' cry many social workers and politicians, especially those left of center. ''The family must have a wider safety net of state aid beneath it. More welfare state, more pensions, more old people's homes, more visiting nurses, more state schools.''
This view, which has dominated political thinking in West Europe since World War II, is being challenged in Britain by Prime Minister Margaret Thatcher. In effect, the prime minister and her own brand of populist, iconoclastic Conservative Party supporters want to boost individual self-reliance and freedom by desocializing the welfare state, at least in part.
They would retain basic services. But they would take the state out of people's lives wherever possible - helping people more, they say, by helping them less in some areas.
Ideas include encouraging the family to take over some of the tasks now done by the state, such as caring for the elderly and the unemployed, and providing discipline as well as care for the young.
At the same time, say supporters of the desocializing program, parents should be given wider choices - by offering vouchers for use at either state or private schools, and by boosting private health care as well as the National Health Service.
''We live in an overcentralized, overtaxed, over-controlled society,'' says one source familiar with the prime minister's approach.
''Other countries might have a heavily state-provided education or health service. We have both, and a lot of nationalized industry as well. Compared to the United States and other countries, we start further back and we have a longer way to go to achieve more individual self-reliance and freedom.''
The implications here could be enormous. The plans remain highly controversial and can start to take effect only if Mrs. Thatcher wins the next general election. But the prime minister is a leader of remarkable force and drive who means what she says, as even her critics agree.
The thrust of the new thinking fits her own wish that Britain return to what she sees as the virtues of the Victorian era - personal responsibility and the freedom to choose.
Her critics, including Labour shadow ministers Neil Kinnock and Gwyneth Dunwoody, are appalled. To them, the Victorian era means the squalor and inequities of industrialization that Dickens fought so hard, and imperialism as well.
What she wants is all very well for the ''achiever'' middle classes from which she herself came, the Labour spokesmen say, but it would leave those in the poorer working class in worse condition.
''Any proposal to cut back on state-provided benefits will inevitably hit the poorest hardest,'' wrote a columnist in the Sunday Observer.
''She wants to reach the 1930s by 1990,'' scoffed Mr. Kinnock, shadow minister for education.
The prime minister takes the opposite view - that it is too much state influence and control that weaken society. The ''nonachievers,'' she says, need to be shown how best to free themselves. In the meantime, they can be given more choice and opportunity to extract the best that the existing state system has to offer.
Mrs. Thatcher has formed a new Family Policy Group, which operates from the white-walled, upper-story inner sanctums of 10 Downing Street itself. It is headed by author and former journalist Ferdinand Mount, a champion of the family as society's enduring defense against the state. He has just written a book called ''The Subversive Family,'' which argues, in part, that the family itself is actually in much better shape than social doomsayers believe.
His new policy group works with a committee of Cabinet ministers. Its task: to find out whether the state can stop the social engineering of Western Europe's Social Democratic and Labour Party activists, and start ''de-engineering'' instead.
In a clear effort to spike its guns, the Conservatives leaked early working papers to the center-left Guardian newspaper earlier this year. Headlines focused on some controversial ideas being proposed by ministers.
For instance, the chancellor of the Exchequer, Sir Geoffrey Howe, wondered if the state could train children to manage their pocket money better. And Employment Secretary Norman Tebbit wanted mothers-to-be encouraged to stay home - an idea that has provoked particular opposition in the press.A working paper urged ministers to look at ''ways of encouraging the development of children . . . into self-reliant, responsible, capable, enterprising, and fulfilled adults.''
Those familiar with the group's operations say that a number of these ideas will probably be discarded. The underlying approach, however, was consistent with Conservative philosophy.
''What we're saying to people,'' says one source, ''is: 'Excuse me, we seem to be in your way. We will try to get out of your way in cases where we don't seem to be helping. In other places, we seem to be helping, so we'll stay in the business of providing roads and police and health services and so on.'
''This is not the same as saying people will be abandoned. . . . In fact, this government has already started to widen individual choice. About half a million council (public) houses have been sold to their tenants. The 1980 Education Act widens parental choice of schools.''
Mrs. Thatcher is not talking about dismantling the welfare state, her supporters say.
''The trouble in this country,'' says one, ''is that the moment you talk about self-reliance and so on, you are accused of wanting to damage free schooling and free health care. . . . We have to get across that there are things that can be done.''
Among specific ideas being considered:
* Trying to ensure that schools are responsive to what parents want rather than being run only by state-paid staff with their own sets of values.
* Adjusting tax and benefit allowances to reward families who look after their own elderly members rather than sending them to state-run institutions.
''Already,'' says one government official, ''95 percent of people over 65 are being cared for by their children or relatives in some way. Only 5 percent are in institutions, and that includes the ill and the blind. To argue that the new policies mean shoving grandmas into dustbins is a misunderstanding.''
* Encouraging families to retake responsibility for the disabled and the hundreds of thousands of jobless youths in the country.
* Stressing the advantages of private health care so that more people can choose the type of care they want. More private doctors help rather than hinder the National Health Service, Mrs. Thatcher contends. They shorten waiting lists for treatment and provide competition that raises standards.
Personally, she would like to see the National Health Service be reduced. But a hint of her wishes last year led to such a political uproar that she was forced to tell her party's annual conference in Brighton that the service was ''safe with us.''
The political storm was a forerunner of the thunderclouds building up over the family planning group.
Next: What else can the state do to leave people alone?