The Journal of Lynton Charles, Fiduciary Secretary to the Treasury

Monday In his high-ceilinged room in Fort Knox, where gilt cherubs chase each other across flaking walls, Mr Brown debriefs us. Like Edward Fox in A Bridge Too Far, his is a cheery homily on the need to get out there this week and give Jerry a hammering. For this is the week in which we and the forces of Conservatism contend for the title of Best Taxers of Britain. From now until Friday, Red Dawn, Ten-foot Timms, A Smith and I will be putting ourselves about on radio and telly, selling our latest great idea: the Low Income Working Families Children's Tax Guarantee Credit.

"We have to emphasise, above all, the acronym FAST," says Mr Brown, sweeping his hair back and addressing a cherub. " F is for family (you really cannot stress that enough); A is for affordability - it's prudent; S is for simplicity; and T is for the fact that we've targeted those who need it most. We're fast. Got it, team?"

"We're fast!" we echo, obligingly.

Monday, later Alistair Darling (Mr Brown's preferred weapon of choice for the big interviews, as Mr Brown is rationing the world to only two personal appearances per parliamentary term) is live on Newsnight, and this - Ed Balls tells me - means that I have to do The World This Evening on Radio 4. Dawn is too fluty (apparently), A Smith sounds strangled and Ten-foot Timms won't fit into the radio car. It's a "four-way" with the presenter, a Tory and some academic. I begin mugging up on the LIWFCTGC and reciting FAST.

Sitting in the Westminster studios, five minutes before the programme begins, I start to feel nervous. The World This Evening is scary. Its presenter, Ernest Moskovitz, is one clever guy and asks tricky questions. Added to which my fellow guests are the brightest Tory in Christendom - the man nicknamed "The Professor" - and the insufferable Adrian Topknot of the Institute for Fiscal Information.

Naturally, the first question I am asked is whether the LIWFCTGC isn't too complex? I say that it is simplicity itself. Any family earning under £32,500 per year, and where both parents are working the full-time equivalent of 25-plus hours a week, will be entitled to a rebate on the main rate of taxation, claimable at the half-year, and worth up to £537.50 per annum. There will be only one form to fill in, and that will consist of just 20 or so simple questions. What could be more straightforward than that?

"Quantum physics?" suggests Moskovitz. The others laugh cruelly.

Tuesday Ed calls and tells me not to worry, and that Mr Brown thought I put up a good fight last night. There are, he adds, some aspects of the LIWFCTGC that may need to be refined. Not least because his parents, both Oxford dons, were listening in and called after the programme to tell him that they hadn't understood a word I was saying. Fortunately, they had understood what The Professor was saying and they hadn't liked it. Thank God for the Tories. What would we do without them?

At home,I watch Ariel Sharon triumph in the Israeli elections. They say that they don't want politicians to behave like politicians, but when you don't, they kill you.

The phone rings.

"Lynton dearest," says a tremulous voice, the voice of a distressed person trying to sound strong, "are you watching Sharon?"

I tell M that I am.

"His career was finished, you know."

"I know."

"But look at him now." He sounds hopeful.

"M," I say, as kindly as I can, "he's 73."

A pause. "Nobody's perfect," says M.

This article first appeared in the 12 February 2001 issue of the New Statesman, Exclusive: how Labour could lose