The road from fruit and veg to purest iron

Robin Butler welcomes a survey of Baroness Thatcher's early years

One of the tasks delegated to the cabinet secretary by successive prime ministers is the vetting of mini-sterial memoirs. The idea is to check that the memoirs do not damage national security, harm Britain's international relations or breach the principles of confidence that their former colleagues or civil servants can justifiably expect.

In that role I read drafts of many ministerial memoirs while I was cabinet secretary, including Margaret Thatcher's. Generally I read them with enjoyment. But the part I discovered that I enjoyed most was the account of their early lives, because this was invariably more personal and human than the accounts of the ups and downs of political life and because it helped to explain the development and the motivation behind the people I had worked with as public figures.

Thatcher has, of course, published her own memoirs in two volumes, The Downing Street Years and The Path to Power . John Campbell is following the same route but in the reverse order. This is the first volume of a two-part biography. It covers the same ground as The Path to Power , starting with its subject's antecedents and upbringing and ending with her entry to 10 Downing Street in 1979.

Campbell explains at the beginning of his acknowledgements that he intended to complete the Thatcher biography in a single volume. He found that the amount of material he had to deal with was too great for that, but he only reluctantly reached the conclusion that he would have to divide the project in two. His confidence in this volume was shaky, even when the typescript was completed. What then is the justification for a two-volume biography covering the same ground as its subject's memoirs and so soon after them?

The justification rapidly becomes app-arent. One of the many fascinations about Thatcher, even for those who knew her well - I was her principal private secretary for three years between 1982 and 1985 as well as cabinet secretary for the last two years of her premiership - is what formed her extraordinary range of diverse and apparently conflicting characteristics. Because her conversation focused on the task in hand, she rarely reminisced. I learned a good deal more about her from this book than I knew before.

The second justification is that the existing literature - and there is a lot of it, as Campbell ruefully points out - is largely divided between hagiography and vituperation. Even the Thatcher memoirs are bound to suffer from the distortions of hindsight and emotion present in any individual's account of his or her upbringing. The temptation is particularly strong for a public figure to pass over in silence people and episodes that cannot honestly be treated with kindness.

Also, in the case of politicians, legends tend to take root, even in the minds of the subject. At a particular moment, politicians may find it convenient to stress some part of their background and, so far as possible, to suppress some other part. When a politically less advantageous period of their experience cannot be suppressed, there is a tendency for subjects to persuade themselves that they did not enjoy it. For example, when President Clinton speaks about Oxford, he tends to refer with great warmth to the day on which an honorary degree was conferred on him rather than to his time as a student, which was politically less advantageous to him, despite the evidence that he greatly enjoyed his time as a Rhodes scholar.

So Campbell tries to cut an objective route through the evidence and, given the tend-ency of legends to obscure the facts and to grow faster than the Cypressus leylandii , it is timely rather than premature to do so. Although it must have been frustrating for him that this is not an authorised biography and that some of those who could have helped him most were unwilling to do so, he has been thorough in examining the vast corpus of material already available and, it seems to me, objective in doing so. He is an acute observer of political life - as one would expect of someone who has written the best biography of Edward Heath as well as books on Lloyd George, Birkenhead, Roy Jenkins and Aneurin Bevan; and he communicates his fascination with unravelling the reality from the image of Margaret Thatcher.

The inconsistencies between reality and image are many. I have surprised friends over the years by citing Thatcher's lack of self-confidence, and it was striking to hear her refer to it herself at a small dinner the BBC gave to mark the television series The Thatcher Years . In consequence, she never took any event lightly, however trivial. Before any visitor arrived at 10 Downing Street, she would take trouble about where they should sit and how they should be entertained. When she talked too much it was often to cover her nervousness.

Yet she listens as she talks. When she visited my college at Oxford earlier this year, one of the students questioned the fairness of her attaching the term illegitimate to children who had had no influence over the circumstances of their birth. She put the questioner down but, several hours later, she suddenly recalled the incident and said: "You know, that student had a point. I must remember it." Another characteristic that surprises those who know only the public image is modesty. She is thought of as dogmatic and bossy, but Campbell brings out her eagerness to learn and her respect for those she regards as expert in their areas. For example, I never knew of any instance when she questioned or challenged the advice of her security staff: they were the experts and she followed their advice.

I tell Oxford friends of what happened when Lord Blake came to Downing Street to offer her an honorary degree while I was her private secretary. I knew nothing of the possibility that Congregation would vote it down, but I could foresee ugly scenes or students blocking the streets and I suggested that it might be better to accept it when she left office. "Look," she said, "if Oxford offers me an honorary degree, who am I to make terms?" There are so many contrasts: between her apparent primness and her thorough enjoyment of a good bit of gossip, between her generally acute perception and her innocence about the meaning of everyday phrases, between the infuriating of colleagues and her sensitivity in finding the caring words to comfort the bereaved or wounded in circumstances that would leave others speechless, between the pragmatist and the uncompromising upholder of principle. What cannot be doubted is her belief in her basic principles and her unflinching courage in holding her corner when she has decided that a battle must be fought - qualities that brought so many people to her banner.

Campbell captures all this and covers the ground well. There are no doubt one or two omissions; for example I was surprised to find no reference to the British Library in Campbell's account of her "big spender" phase as secretary of state for education. But this book is a fascinating and highly readable account of a major and paradoxical figure (although the subtitle, "The Grocer's Daughter", is belittling in my view). I look forward keenly to the story of the Thatcher premiership in the second volume.

Lord Butler is master, University College, Oxford.