LORD JOSEPH was widely acknowledged as the leading Conservative political philosopher of his generation. He was the intellectual driving force behind Thatcherism, and it was he more than any other politician who paved the way for Margaret Thatcher 's election in 1975 to the leadership of the Tory Party.
Baroness Thatcher said, after his death was announced yesterday morning: "Keith Joseph understood that it was necessary to win again the intellectual argument for freedom, and that to do this we must start from first principles. He was, in some ways, an unlikely revolutionary. For all his towering intellect, he was deeply humble. He spoke out boldly, however hostile the audience. Yet he hated to give offence. Above all, his integrity shone out in everything he said and did. His best memorial lies in theyounger generations of politicians whom he inspired. But for me he is irreplaceable."
Testimony to the profound intellectual debt Lady Thatcher owed Lord Joseph came in the letter she wrote to him when he resigned as Secretary of State for Education in 1986: "You more than anyone else were the architect, who, starting from first principles and involving many people, shaped the policies which led to victory in two elections. Our debt to you is great indeed."
It was the last ministerial post he held. In 1987, he was made a life peer.
Many senior politicians expressed their sadness at his death. Lord Tebbit, the former Tory party chairman, said: "I would like to say how enormously sad I am that one of the most generous, kind and able politicians of our time has been lost to us. The happiest period of my life in government was the eight or nine months during which I worked for Keith as his junior minister in the Department of Industry.
"There are too few like him. He never made up his mind rashly or intemperately and it was always his wish to be as fair to his opponents"
Lord Joseph was born in 1918.
The only child of a rich and cultivated Jewish family, he gained a first in jurisprudence at Oxford and then did war service as a captain in the Royal Artillery. He was wounded during the Italian campaign and mentioned in dispatches.
He once said that he was a slow developer, and had spent his time at university reading poetry and watching cricket - nothing that hinted at the intellectual struggle he was to wage later: to solve the problem of the persistence of poverty. It was this that led him to articulate during the Sixties and, to most effect, the Seventies, a vision of British society in which the state participated as little as possible, and people learnt the value of self-reliance.
After the war Lord Joseph qualified as a barrister, but he never practised. He joined the family building firm, Bovis, of which he later became chairman His political career began in 1956 when he was elected MP for Leeds North East. In 1970, after serving in junior ministerial positions, he was appointed Secretary of State for Social Services by Edward Heath, who was impressed by his commitment to resolving social problems. But it was from Mr Heath's cabinet that Sir Keith Joseph launched his campaign t o redirect Conservative political thinking.
Sir Keith approached politics with all the academic rigour that had earned him a Fellowship of All Souls College, Oxford, and led him to found the Conservative Party's Centre for Policy Studies.
He earned a reputation for logic and for fundamentalism in his thinking which was refreshing in the early Seventies - at a time when the intellectual vigour of Britain's political life seemed to have disintegrated.
He argued that there was a detailed and intimate relationship between economic policy and the well-being of individuals in society. He believed, for example, that low productivity and bad management contributed to the moral degeneracy of society.
He believed, therefore, that the key to a happy society was not the maintenance of full employment, which was then the principal objective of both Tory and Labour governments, but the control of inflation.
A disciplined economy in which jobs were real - not, in other words, merely the result of government subsidy - would create a stable society. The political implications of such thinking were vast: privatisation, cutting back on public sector spending, ruthless management of interest rates.
Lord Joseph was regarded by many as a possible successor to Edward Heath but, in 1974, he made a speech which effectively ruled him out.
In this famous speech, delivered at the Grand Hotel in Birmingham on 19 October, he warned that there was a "cycle of deprivation" which trapped the poor in endless poverty because they were less capable than richer social groups of controlling the size of their families.
"The balance of our population, our human stock, is threatened," he said. "A rising population of children are being born to mothers least fitted to bring children into the world." His opponents treated the speech as if it was a call for mass sterilisation. He was vilified.
A month later, he walked into Mrs Thatcher's office and told her that he would not be challenging Edward Heath. He thus left the way clear for her. Over the next year, the two of them took effective control of the party. Lord Joseph, alderman of the City, underwriter at Lloyd's, livery man of the Vintner's Company, may have seemed an odd partner for the daughter of a Lincolnshire grocer, but she was a symbol, to him, of what could be achieved by sheer application.
His ideas may have been controversial, but those who worked with him, remember him as a man devoid of vanity.
Lord Healey said yesterday: "He was a very nice man and really a friend of mine because we both had Commons seats in Leeds. But his political ideas were bizarre and damaging."
Lord Joseph was a keen cricket fan and became a member of the MCC. He also played a major part in many Jewish organisations, including the Central British Fund for Jewish Relief and Rehabilitation. During one recent interview, he said: "I came into politics 35 years ago to improve life for the majority of the British people, particularly the poor and downtrodden."
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies