Making some sense of our world

National Science Week isn't just some celebration fit for anoraks - it's for everyone, says Tom Wilkie

Dr Watson was once deeply shocked to discover that Sherlock Holmes did not know that the earth went round the sun. Nor did he care.

A master of contemporary forensic chemistry, Holmes told Watson that astronomy was simply not useful knowledge for him. That dismissive judgement by Britain's greatest fictional detective comes into the hard focus of reality this week now that Britain's third national festival of science, engineering and technology - SET '96 - is in full swing.

From trips to the labs behind the showcases at the Natural History Museum in London to late night table-top demonstrations of science at the Insomnia Cafe in Glasgow, more than 5,000 events are being held around the country.

And yet, there are questions. One of the most basic is why should anyone who is not intending to become a scientist actually get interested?

In his lectures on the two cultures, CP Snow set the second law of thermodynamics as his criterion for scientific literacy. But it is rather difficult to see how knowing that the entropy of the universe increases (which is one formulation of the second law) really helps with defrosting the fridge. Personally, having been trained as a physicist, I was once able to solve James Clerk Maxwell's equations for the propagation of electromagnetic waves - which is how radio and television are transmitted to my home - but I cannot programme the video recorder. I knew the theory of electron transport in semiconductors, but it doesn't help me with the intricacies of wordprocessing on Microsoft Word - even though my computer depends on semiconductors for its operation.

Functional literacy in technical society does not depend on a knowledge of scientific facts. Nor does living in the modern world depend on what might be called a scientific attitude of mind. We live in a society founded on division of labour and, outside the laboratory, the scientist's disciplined curiosity is a positive hindrance to the smooth running of our lives.

For example, none of the distinguished academic scientists who from time to time take the train from Oxford to London would expect to have the right first to tap the wheels of the train to verify their integrity.Even in matters of life and death, we subcontract our fate to others.

It is probably not possible even in principle for any one individual to understand all the science and technology that go into making a transatlantic plane flight possible and safe. To do so would require enough metallurgy to understand the alloys used in modern airframes, a knowledge of modern jet engines, the electronics of the control and navigation equipment and of the software involved in the air traffic control system which guides aeroplanes. No one individual could possibly comprehend all that.

In fact, the most important questions about the safety of aeroplanes are social, not scientific. The laws of aerodynamics apply equally to aircraft belonging to Lufthansa or to Aeroflot. Yet Lufthansa's planes have not fallen from the sky with the disconcerting frequency of those belonging to the former Soviet Union's airline. The outcome is different although the science is the same; what differed was the social institutions to ensure engineering quality and the "safety culture" of the German civil aviation industry and that of the Soviet Union.

When a train crashes on the west coast mainline near Stafford, we do not worry that the laws of physics might have broken down. Instead, our response is social, we worry that privatisation might be weakening safety standards and we seek to examine the procedures in place at Railtrack.

What, then, is science, and national science week, for? The conventional answer is a utilitarian one. Only those who understand science, it is argued, will be able to cope with the world around them in the 21st century because that will be a world totally dominated by the products of science.

And yet. Last week, representatives of the Save British Science Society pointed out that British industry clearly does not want science or scientists. For UK companies' investment in science to match that of our more successful competitors, they would need to recruit at least 70,000 more scientists and engineers. If SET '96 enthuses children so much that they decide to make a career in science, they will soon find themselves jobless.

That said, there are good reasons why people should take an intelligent interest in science. One is to make sure that we are in control of what science does. There can hardly be anyone who has not directly or indirectly been affected by the discovery in the late Thirties of atomic fission. This seemingly obscure branch of applied quantum mechanics led both to the atomic and the hydrogen bombs that have dominated post-war politics and cast long shadows of fear over our lives.

As the century draws to its end, there is another scientific development that promises to touch our lives more nearly and more intimately: the startling advances in molecular genetics. These developments have already given rise to genetically engineered food on our supermarket shelves; human beings undergoing gene therapy to correct inborn defects, not to mention moral disquiet over the "cloning" of sheep.

Properly understood, these developments bring, in the worlds of the late, great medical researcher Sir Peter Medawar, "the Hope of Progress". But scientific knowledge, like the sword of justice, has a double edge: it can be used for ill as well as for good. We need to understand not so much the scientific details of, say, sheep cloning, but the broader question of how scientific discoveries come into our lives and how from among the options for the future we can choose the ones we feel will be beneficial.

Perhaps the best reason for non-specialists to try to understand science is a cultural one without any pragmatic value. It is simply that science provides a profoundly satisfying way of looking at and making sense of the world in which we live. It tells us that we can make some sense of the world, that it is not all arbitrary and chaotic. The astonishing thing is not that we know so little but that we can make so much sense of the universe.

For example, there has been life on earth for about 3.5 billion years. Throughout all that time, its growth and its development has been directed by the double helix molecule of DNA and by its close chemical relative RNA. Amid all the diversity of life on earth past and present, we are the first creatures in existence to be aware of the existence, structure and function of this thin filament of life.

This week, that is indeed something to celebrate.