When Alan Clark confided in his diary, “How inextricably woven are the different strands of greed, ambition, cowardice and idealism”, the only quality listed which could not possibly refer to himself was idealism. This selection of entries for the years 1972-82, preceding in time the celebrated volume which made Clark notorious for his frankness, and covering his entry into Parliament and his escapades once he arrived there, is gruesomely frank in its revelation of the contemptible qualities which comprised, overwhelmingly, its author’s character.

On rare occasions he seems to realise how awful he is, as when he admits to “sneaking and troublemaking” when, having obeyed the Tory whips by trying to wreck a Commons speech by Edward Heath, he then finks on the whips by writing a letter to Heath confessing his misdeed. Generally, however, he is too busy denouncing the motes in his Conservative colleagues’ characters to realise the shortcomings in his own.

Thus, James Prior and John Major are “toads”, Michael Heseltine is “odious”, Chris Patten “bumptious”, Peter Walker a “rubbery little s”, John Gummer an “oily little creep”, and Norman Fowler “common”. He “loathes” his Plymouth constituency, to which he hates to go and where, once there, he is reluctant to hold surgeries.

Nor is it only politicians who attract vituperation. While he is overwhelmed with conceit at attending a Buckingham Palace garden party, an event to which all MPs are routinely invited, some members of the Royal family incur his invective. Princess Margaret is “ugly, dwarflike, lecherous and revoltingly tastelessly behaved”. His own father, the art connoisseur Lord Clark, for whose death he can scarcely wait, comes in for the lash as “very shifty and unpleasant”.

Yet, as I read on, I came to cherish Clark. For, while he was undoubtedly a bounder and an idler, he emerges from this book as a classic minor character who would have been thoroughly at home among the dramatis personae of Restoration comedy, named, perhaps, Mr Sneerwell.

Once in Parliament, he pursued his yearning to be promoted to the government of Margaret Thatcher - one of the very few people for whom he had any time, awarding her the sobriquet of “The Lady” and the bouquet of being “beautiful” - with a series of inept manoeuvrings. He voted for himself twice in an election for a trivial party office after which he lusted and which he nevertheless failed to win.

He was adept at penning toadying letters, telling the “odious” Heseltine “how much I looked forward to . . . working under him, etc. etc.” He pledged loyalty to William Whitelaw, the Home Secretary, while surreptitiously conniving to have him sacked from the government. Ingratiating letters were delivered by the cartload to Ian Gow, Margaret Thatcher’s Parliamentary Private Secretary.

His crawling to Mrs Thatcher providesthe most delightful episodes in this perversely readable book. After Mrs Thatcher had announced to the Commons the Argentine surrender in the Falklands war, “I rose rapidly, pushed my way through the crowd at the bar of the House and shot round through the “Aye” Lobby to catch the Prime Minister as she emerged at the back of the Speaker’s Chair . . . I rushed up and said to her: “Prime Minister, only you could have done this; you did it alone, and your place in history is assured.” Not surprisingly, after this extraordinary specimen of grovelling, “She looked a little startled.”

It was not until several months after this volume ends that Mrs Thatcher rewarded Clark for his shameless self-abasement by appointing him to the lowly office of Parliamentary Secretary (which he accepted with alacrity after assuring himself in these pages that nothing less than the rank of Minister of State would do). He attained this modest eminence after betraying every colleague whom he judged obstructed his ambitions; but then, nothing more - or less - could be expected from a man who self-confessedly operated on the principle: “It is always tricky opposing a friend - especially if you are not certain of the outcome.”

GERALD KAUFMAN