You are wrong, Mr Blair: it is you who is prejudiced about science, and it is the people at large who have respect for the evidence

The Prime Minister believes in the unfailing beneficence of high tech. <strong>Colin Tudge,</strong>

There was much to warm the heart in Tony Blair's address on science to the Royal Society on 23 May. We shouldn't be afraid of it, he said. The high tech that comes out of science can truly benefit humanity and indeed has become essential. New ways of doing things should not be dismissed a priori, not even those apparently as radical as genetic engineering. We should not allow our "prejudice" to deny us a better life. We should spend more on research (and "today the science budget is increasing by 7 per cent per year in real terms"). Yes, moral awareness should keep pace with technical power - and this is happening. The quandaries of embryonic stem cell research were sifted by the appointed ethical committee. Now we need public debate to keep things on track. We should step up science education.

So why, as a devotee of science these past 40 years, do I find Blair's reassurances so unreassuring? His vision of science, of what it really is and what it can do for us; his belief in its capacity not simply to make us richer but truly to improve our lives; the absence of introspection, his self-assurance, which reflects that of the scientists themselves; his (and the scientists') deep conviction that if people at large ("the public") have misgivings, then it is because we have failed to understand; the broad notion that "public trust" is simply a matter of public relations - all this is chilling. Science is what I spend my life on, but I want no truck with the insouciant, confident monster that Blair (and much of the scientific establishment) construes it to be.

There is a worrying, "not me, guv", false innocence even in Blair's apparently unexceptionable claim that "science is just knowledge" and so is morally neutral. Giving ourselves carte blanche to find things out is itself a moral decision, as many a priest would point out.

Besides, although "science" means "knowledge" etymologically (scientia), it now connotes much more. It seeks to find out how things work, by testing formal hypotheses: constrained by facts, logic and especially maths, it is the ultimate exercise in rationality. Rationality is necessary for survival and is in many ways attractive: the Apollonic tradition, as opposed to the Dionysiac. But rationality is itself an attitude, and it is a moral decision to put store by it. It is rationality, for example, that justifies experiments on animals in the face of aesthetic repulsion. Voltaire made this point long before any modern "animal libber".

One of the things that bothers people is the apparent unwillingness of scientists to engage in serious discussion on such matters, man to man as opposed to de haut en bas; and it does not help if they or their apologists begin by denying that there is anything serious to discuss.

On the whole, though, Blair was more down to earth: "Our goal is prosperity for all through successful business using excellent science. . . . Britain can be as much of a powerhouse of innovation - and its spin-offs - in the 21st century as in the 19th and early 20th." We're getting there: "In 1999-2000, 199 companies were spun off from our universities, compared with 70 a year in the previous five years." And: "The biotech industry's market in Europe alone is expected to be worth $100bn by 2005."

It is true that science, high tech and modern commerce are tightly interlocked. The kind of technology to which science gives rise is high tech by definition. Science and modern capitalism have grown up together since the 17th century, in a feedback loop: capital finances the science that provides the high tech that produces the industry that provides more science and so on, as Newton noted with approval. This loop has become the engine of the modern world. The societies that thrive best (in material terms) are those whose governments ride the engine most adroitly. This, rather than ideology, determines who comes out on top.

But what should be of prime concern to a government with "Labour" in its title is whether this whirring engine of high tech coupled with material prosperity necessarily raises general well-being. In an unalloyed capitalist world, industry can finance only the research that produces the things that can be sold for the most profit. If it does not, the shareholders go elsewhere. So the engine, left to itself, produces oodles of goods for people who can afford them but do not necessarily need them. So far, it has not proved able to provide drugs against Aids for poor South Africans, or to support research that will provide drought-resistant crops for poor South African farmers.

New Labour seems to believe as firmly as Margaret Thatcher did that the market is bound to deliver. Yet, if science is truly to operate for the betterment of humanity at large, it cannot simply be left in the hands of commerce. A prime concern for humanity - perhaps the most important single task, in the long term - is to liberate science from the feedback loop in which it has grown up. Blair's government is not only failing to do this, it gives no sign that it acknowledges the problem. But people at large understand it perfectly well: they believe not simply that the leaders and experts have got it wrong, but that they have less feel for the deep issues than many of the rest of us.

Yet all Blair seems to see in public misgiving is signs of "prejudice against science", which, he tells us, would be "profoundly damaging". He wants "to reach my judgements after I have the facts and not before". We need "a culture that values a pragmatic, evidence-based approach to new opportunities".

Again, evidence is certainly a good thing. But there is little evidence from the past 200 years that people at large are prejudiced against science, or against the technologies it produces. Steam power in general and the railways were embraced avidly; they transformed the western world, and then the eastern, within decades. Electricity, radio, the telephone, the motor car, the jumbo jet, television, CDs, drugs and food additives of all kinds have been seized on so eagerly that Blair might, with at least equal fervour, have urged restraint; after all, it may turn out to be true that mobile phones fry the brains.

All these high technologies had their initial detractors ("lightning conductors, invented by Benjamin Franklin, were initially torn down", Blair reminds us), but none of the important advances was seriously held up by public reluctance. Doubts have persisted only where the facts - the evidence - suggests that doubt is absolutely justified. Perhaps nuclear power is necessary, but you would have to be mildly deranged not to take seriously the threat implied by Chernobyl or Three Mile Island.

Today's symbols of progress, and also of public prejudice and intransigence, are genetically modified organisms (GMOs). Blair tells us that he "can find no serious evidence of health risks", and in this he is probably justified. The direct risks are probably low. Again, however, he has missed the point.

Nobody can deny that there are some theoretical risks, notably ecological. That is why we have the trials that have prompted some people to pull up GM crops. But "the public" would like to know why these risks are being taken at all. They are told that genetic engineering alone can provide the drought- and pest-resistant super-crops that we need to feed ten billion people by 2050.

This is just not true. I am writing a book about agriculture and have found plenty of evidence that it, and we, need excellent science. But it is also clear that what has enabled the human species to flourish is not the science of agriculture but its traditional craft: good husbandry, which means raising the right plants and animals in the right places, in ways that minimise the spread of infection.

The evidence shows that science does good when it helps good farmers of all kinds to do even better the things they already do well. But history demonstrates again and again that any attempt to flout good husbandry invariably proves disastrous. Homer knew this. The Roman Columella wrote about it. Stalin demonstrated it, and so did the creators of the American dust bowl.

Government policy since the Second World War has primarily been designed to reduce the cost of production (which is not the same as reducing the price of food), and, in this, the basic rules of husbandry are flouted systematically. Science makes this possible. The policy is frightening, and the role that science plays in it is shameful. Blair is right to point out that BSE did not result directly from science misapplied. But BSE, and foot-and-mouth disease, did result directly from the cut-price production policies to which science has become central.

Genetic engineering may or may not have a part to play in feeding the world in future, but, at present, its role is almost entirely to abet a cut-price, profit-based agricultural policy that, as the decades pass, will surely prove disastrous. There is no evidence at all - absolutely zilch - that GMOs so far have contributed one jot of serious, lasting value to the world's food security, or are liable to do so in the near future, or that they will do anything truly worthwhile that could not be achieved by conventional breeding (and yes, genetic engineering is qualitatively different even from the most advanced conventional breeding).

In other words, those who truly have respect for evidence would be very cautious indeed about GMOs; not about whether they are more dangerous to our individual health than, say, the average parsnip, but whether they truly have any serious role to play in feeding the world, and whether, if they are simply a commercial expedient, we should countenance any risk at all. It is not evidence but prejudice - an uncritical belief in the need for high tech and its unfailing beneficence - that drives so many professional scientists, and Blair himself, to advocate GMOs so vehemently. One reason why "the public" is so reluctant to rely on experts is that the experts so often seem to live in their own fantasy worlds. In general, where people have been happy to follow the experts (as they did into the age of steam and the age of computers), they have been right to do so; and where they have been seriously reluctant (nuclear energy), they have been right, too.

So what of Blair's final plea, for more and better science education? I'm all for it. I would love the universities and schools to ask what science really is, and what it is not; what it can and should do; what it cannot and should not do. This would be a broad education, with facts and maths and hard philosophising, all set in its properly metaphysical context. New Labour, however, has plans for "about 25 specialist science colleges" and "a new applied science GCSE".

In short, the big metaphysical and moral decisions have already been taken. Science is a purely materialist pursuit, its role is to support British industry in the face of competition, and that is self-evidently a good thing. Anyone who has any doubts on this score is prejudiced and foolish. There is no point in the public debate. It's already over.

Colin Tudge's The Variety of Life and In Mendel's Footnotes are out in paperback