Now in his late sixties he is a casting a nostalgic backwards glance to a time when before the dominance of the TV

Now in his late sixties, he is a casting a nostalgic backwards glance to a time when, before the dominance of the TV cooks, he himself was a pre-eminent cookery figure of the day.In the early Sixties, Deighton, not long out of art college, was indulging his passion for cooking. Those with long memories will know that a cookbook from Len Deighton is far from being a new departure. Recent trilogies have included Faith, Hope and Charity. And now a cookbook If it seems like vanity, it isn't at all. A string of best-sellers followed such as Horse Under Water and Funeral in Berlin, a number of books set around the Second World War and the novel Winter, the story of a German family from 1900 to Hitler's downfall. Deighton broke the mould of upper-class Bond-style agents when he created anti-hero Harry Palmer, an insubordinate Cockney. The first, which made his and Michael Caine's name, was The Ipcress File.

Deighton is the author of over 30 thrillers, the most successful of which have been filmed. The fact that his latest is a cookery book, a Basic French Cookery Course, makes it even more remarkable. A new book from one of Britain's most popular writers, Len Deighton, is always an event. Thus only eight out of 108 with a positive test will have the disease, that is less than eight per cent! The patient, contrary to what most doctors think, should be quite reassured.If you got it right, risk patting yourself on the back but be careful not to pull a muscle - life is risky.Lewis Wolpert is Professor of Biology as Applied to Medicine at University College London.

Let us take at random 1,000 people, then we expect 10 to have the disease Of these 10 only eight will be detected by the test Tests on the other 990 will give 100 false positives. They emphasise the importance of integrity in collecting evidence, and openness in explaining how scientific advice has been obtained and interpreted.But back to our doctor. Recognizing the significance of science in policy-making, he has put down guidelines for the Government. And rightly so considering the recent BSE and E coli events.All this makes the new document prepared by the Chief Scientific Adviser, Sir Robert May, particularly welcome.

Even so, surveys show that compared to the trust people have in politicians, scientists do very well. No wonder the public puts greater trust in scientists who work for environmental pressure groups. Should one trust scientists who work for institutions with a vested interest in denying the risk, like tobacco companies? It matters who the paymasters are. So if one trusts scientists when they report risks, why should one be so suspicious when they estimate how serious the risk may be?The key issue is one of trust. But here lies a certain paradox, for it is only because of science and scientists that we know about the risks at all. Moreover, science and scientists are not really to be trusted.

There is also often an explicit or implicit criticism of science for having created these risks in the first place. Anything attached to the words radiation or nuclear has become taboo. Those from the social sciences who comment on public perceptions of risk rightly point out that the public's perceptions are often not the same as those of scientists. The media is entirely responsible for public refusal to have anything to do with irradiated food, even though it could bring benefits and there is no evidence that it is dangerous. Daily deaths on the road go unnoticed while dog bites child or man bites dog make the headlines. Exceptional events are given excessive prominence in comparison to common ones.