by Stephen Hawking

Whether we like it or not, the world we live in has changed a great deal in the last hundred years, and it is likely to change even more in the next hundred. Some people would like to stop these changes and go back to what they see as a purer and simpler age. But as history shows, the past was not that wonderful. It was not so bad for a privileged minority, though even they had to do without modern medicine, and childbirth was highly risky for women. But for thevast majority of the population, life was nasty, brutish, and short.

Anyway, even if one wanted to, one couldn't put the clock

back to an earlier age. Knowledge and techniques can't just be forgotten. Nor can one prevent further advances in the future. Even if all government money for research were cut off (and

present government is doing its best), the force of competition would still bring about advances in technology. Moreover, one cannot stop enquiring minds from thinking basic science, whether or not they are paid for it. The only way to prevent further developments would be a totalitarian state that suppressed anything new, and human initiative and ingenuity are such that even this wouldn’t succeed. All it would do is to slow down the rate of change.

If we accept that we cannot prevent science and technology from changing our world, we can at least try to ensure that the changes they make are in the right directions. In a democratic society, this means that the public needs to have a basic understanding of science, so that it can make informed decisions and not leave them in the hands of experts. At the moment, the public has a rather ambivalent attitude towards science. It has come to expect the steady increase in the standard of living that new developments in science and technology have brought to continue, but it also distrusts science because it doesn't understand it. This distrust is evident in the cartoon figure of the mad scientist working in his laboratory to produce Frankenstein. It is also an important element behind support for the Green parties. But the public also has a great interest in science, particularly astronomy, as is shown by the large audiences for television series such as Cosmos and science fiction.

What can be done to harness this interest and give the public the scientific background it needs to make informed decisions on subjects like acid rain, the greenhouse effect, nuclear weapons, and genetic engineering? Clearly, the basis must lie in what is taught in schools. But in schools science is often presented in a dry and uninteresting manner. Children learn it by rote to pass examinations, and they don't see its relevance to the world around them. Moreover, science is often taught in

terms of equations. Although equations are a concise and accurate way of describing mathematical ideas, they frighten most people. When I wrote a popular book recently, I was advised

that each equation I included would halve the sales. I included one equation, Einstein's famous equation, E = mc2. Maybe, I would have sold twice as many copies without it.

Scientists and engineers tend to express their ideas in the form of equations because they need to know the precise value of quantities. But for the rest of us, the qualitative grasp of scientific concepts is sufficient, and this can be conveyed by words and diagrams, without the use of equations.

The science people learn in school can provide the basic framework. But the rate of scientific progress is now so rapid that there are always new developments that have occurred since one was at school or university. I never learned about molecular biology or transistors at school, but genetic engineering and computers are two of the developments most likely to change the way we live in the future. popular books and magazine articles about science can help to put across new developments, but even the most successful popular book is read by only a small portion of the population. Only television can reach a truly mass audience. There are some very good science programs on TV, but others present scientific wonders simply as magic, without explaining them or showing how they fit into the framework of scientific ideas. Producers of television science programs should realize that they have a responsibility to educate the public, not just entertain it.

What are the science-related issues that the public will have to make decisions on in the near future? By far the most urgent is that of nuclear weapons. Other global problems, such as food supply or the greenhouse effect, are relatively slow-acting, but a nuclear war would mean the end of all human life on earth within days. The relaxation of east-west tensions brought about by the ending of the cold war has meant that the fear of nuclear war has receded from public consciousness. But the danger is still there as long as there are enough weapons to kill the entire population of the world many times over. In former Soviet states and in America, nuclear weapons are still poised to strike all the major cities in the Northern hemisphere. It would only take a computer error or a mutiny by some of those manning the weapons to trigger off a global war. It is even more worrying that relatively minor powers are now acquiring nuclear weapons. The major powers have behaved in a reasonably responsible way, but one cannot have such confidence in minor powers like Libya or Iraq, Pakistan, or Azerbaijan. The danger is not so much in the actual nuclear weapons that such nations may soon possess, which would be fairly rudimentary, though they could still kill millions of people. Rather, the danger is that a nuclear war between two minor powers could draw in the major powers with their enormous arsenal.

It is very important that the public realize the danker and put pressure on all governments to agree on large arms cuts. It probably is not practical to remove nuclear weapons entirely, but we can lessen the danger by reducing the number of weapons.

If we manage to avoid a nuclear war, there are still other dangers that could destroy us all. There’s a sick joke that the reason we have not been contacted by an alien civilization is that civilizations tend to destroy themselves when they reach our stage. But I have sufficient faith in the good sense of the public that we might prove this wrong.

(Note: The speech was given in Orviedo, Spain, on receiving the Prince of Asturias Prize in October 1989.)