I first became aware of Peter Townsend, who died recently at the age of 81, when as a young journalist I read an article in the Guardian about the three professors - the others were Brian Abel-Smith and Richard Titmuss - who were going to assist the incoming Labour government in abolishing poverty.  I think that they were then engaged with Richard Crossman in constructing a fair superannuation policy; and they wrote a classic Fabian pamphlet.

Well, as we all know, it all came to an abrupt halt.  But Peter didn't.  He was very soon disillusioned and co-founded the Child Poverty Action Group in 1965 to mobilise around the cause of eradicating poverty, the Webbs' 2,000 or so people in the country who really counted. The ‘Child' was added to the title of the group to give it emotional weight, but the aim was always much broader.

Peter transformed himself into a tireless campaigner. He took the chair at CPAG and wrote and spoke seemingly everywhere, adding his considerable presence, intelligence, charm and rage to what became an endless odyssey. It is not too much to say that he inspired me. I have been an egalitarian ever since I can remember, but at first I wanted to be a journalist as well.  That ambition didn't really survive encountering other journalists, on The Times where I was working and elsewhere. Peter's work had the opposite effect, and I joined CPAG to run its citizen's rights office.

There was real tension between Peter and Frank Field who was then CPAG's brilliant director: it was not so much that they both liked to be in the forefront, more that they disagreed on the tactics (Frank the shrewd pragmatist) and strategy (Peter the seer).  There was also tension between Frank and me (now long gone; we are friends) as I was determined to achieve reforms of social security, and Frank took a cautious view of their acceptability.  Peter managed to be a tactful ally as well as an inspiring presence.

In 1979, Peter published Poverty in the United Kingdom, a huge undertaking that would have justified anyone's life on its own.  He had been working on it for some 10 years and still it had the quality of being rushed out.  It is one of the few big books I have read from cover to cover. I am not qualified to be an academic commentator on it.  All I can say is that it seemed to me to combine a masterly concept that justified the idea of ‘relative poverty' with survey evidence that people in general shared this more generous view of poverty and sufficient hard facts to move anyone. Anyone that is but Mrs Thatcher and, I fear, those who come after her in the elite Cameron caravanserai.  Poverty in the United Kingdom remains a hugely influential work, and it had an immediate impact, leading to some very good LWT documentaries among much else.

At about that time I was asked by Pan Books to write a book on the future of the Labour Party and the left.  I persuaded the publishers that a joint book would carry more weight and Peter joined me, Robin Cook, John Griffith, Jimmy Reid, Frances Morrell and Francis Cripps as a joint author.  Peter was very much a central figure in the debates and drafts that culminated in Manifesto which was published after Robin Cook left us.  He wrote the chapter on wealth and income, containing the proposal that there should be a linked minimum and maximum wage - we set the maximum at £28,000.  The book was interpreted by the media as a ‘Bennite bible', much to Tony Benn's annoyance, and ours.  The idea of a maximum wage caught the media's attention, but the book was a failure in Pan's view, selling a mere 16,000 copies.

Peter had another proposal that we rejected. He wanted really to set about equalising wealth and suggested that people's commissions should be set up across the country to assess the wealth of individual rich people.  We felt that this was too Robespierrean an idea.  It did however illustrate for me that quality of radical purity that animated Peter's life and that, I think, made that life uncomfortable at times for him as it did for many others.  It should also be said that it did not prevent him from enjoying the pleasures of life; and he frequently displayed a gaiety in company that made working with him fun.

It was however his radical quality  that I believe drove Peter on in a protean career in which Poverty in the United Kingdom and his work for CPAG were only two elements.  He carried out significant research on the quality of life for old people, disability and health inequalities - in the Black report - and took his campaigning activities onto these new fronts of inequality in our society.  There is no doubt that he created a vast store of knowledge and inspiration that will live on in continuing efforts to make that society more equal (and that has even touched the New Labour project). As Professor Alan Walker, one of his disciples and colleagues, has written, his work ‘inspired thousands and benefited millions'.