In an ideal world, the public and its politicians would appreciate how rarely good scientists make valid predictions, but how often correctly designed experiments eliminate error. The error-correcting ability of the scientific method distinguishes it from all other forms of inquiry, and makes it superior to them. No matter how passionately a scientist believes in their hypothesis, and no matter how intelligent, ingenious, or appealing the hypothesis may be, the experiment can prove it wrong.

Most competent scientists make hypotheses every day, and thousands of hypotheses in a lifetime. It is rare and lucky, if one of these hypotheses turns out to have a general relevance, and an ability to withstand vigorous experimental challenges. The value of a hypothesis is uncertain, until it has been tested. The judgement of quality is entirely retrospective.

Therefore, do not suppose that science has a logically predetermined direction. Research whose results are pre-determined is technology, rather than science. Do not ask scientists to be seers. Scientists are no better at predicting the future than anyone else, although they might be able to eliminate some nonsense, on the basis of known facts. Nor should scientists be given priority, in ethical and political decisions. Scientists' opinions have the same value as those of other citizens.

There are two things that a sensible nation can demand of its scientists. The first is to make transparently clear, without advocacy, the unvarnished facts. The second is to test, dispassionately, interesting or potentially useful hypotheses. Both of these activities require protection from outside pressures - whether economic, managerial, political, ideological, religious, or commercial. These activities also demand a commitment to resist internal pressures of the same kind.

Given this protection and commitment, scientists will work long hours for little pay, advancing the nation's knowledge and skills. The alternative, in the long term, is ignorance and incompetence. It is time to put the scientists back in their ivory towers.