He was periodically tortured in judging whether to put intellectual integrity before or after party expediency or loyalty. The story of his "mea culpa!" when passing tower-blocks may be apocryphal, but it expresses his sensitivity and responsibility where he thought he detected failure.
We first met in 1964 after the Conservative defeat when he asked to come to the Institute of Economic Affairs in the search for ideas to ponder during the years in opposition. He was made to feel that, with few exceptions like the abolition of resale price maintenance, we did not think much of the Conservative efforts since 1951 to liberalise the British economy.
Nothing emerged from his rethinking in the six years of Labour rule to 1970. But he returned after the Conservative defeat in 1974 on the same mission, this time more determined to escape from the four further years of Conservative failure.
His second mission seemed to fortify his determination, declared at a dinner to which he invited Ralph (now Lord) Harris and me at Locketts restaurant in Marsham Street, to establish an office that would "carry on where the IEA left off" by translating the analyses of IEA economists into proposals for government policy.
It emerged as the Centre for Policy Studies. We warned him it would not be easy and he would have to be tough.
His role in applying the classical liberal thinking he acquired from the increasing output of the IEA, then still the only market-oriented "think-tank" of its kind, in tutoring Margaret Thatcher in the following years seemed to me to turn him from one ofthe most considerable Conservative intellects to the dominant mind in the policies of the 1980s.
His interest in "the condition of the English people" was reflected in the Government departments he had led in education, medical care, and housing. His seat in Leeds must have taught him of the conditions in which the common people lived. At the 1982 Conservative Party conference, when he reported on his investigations into the possibility of an education voucher to give the working classes the power to escape from bad schools, he declared, in tones that came as near as he could muster to eloquent party populism: "The Conservative Party does not exist only for the rich and the clever". But, alas, in 1983 he had again to acknowledge defeat, this time not least by Conservative activists in the Hampsteads of England who were not going to have the parents of the Hackneys invading "their" state schools which they had to themselves by paying the high housing costs of the Hampsteads.
He was always anxious for the integrity of his arguments. When I told him that the IEA required its authors to document their analyses thoroughly by sources and references that could be checked by critics, and added "We fight them in the footnotes", he delightedly quoted the alliteration when introducing me to strangers.
He was a sentimental man. At a party to celebrate his contribution to the 1987 General Election victory, praise from friends to disregard the sometimes harsh criticism from journalists (such as "the mad monk") drew tears he tried to disguise but failed.
His sentimentality meant that he could not apply political steel, especially to obstructive civil servants. He could not follow the lesson for ministers pointed by RHS Crossman in his memoires on the battle between permanent professional bureaucrats and transient, amateur ministers: "Select a few, a very few issues, and in those issues be bloody and blunt".
Keith was not bloody or blunt. But he has left the new Conservatism as his political legacy.
The author is a founder president of the Institute of Economic AffairsReuse content