Science and Freedom. April 23, 1956 (1956s.17)

Science and Freedom by Linus Pauling

Yale Law School Forum 8 PM 23 April 1956 New Haven, Conn.

Mr. Chairman, Ladies and Gentlemen:

I want first of all to thank the Yale Law Forum for having invited me to speak tonight. I shall not say that I am happy to be here. There is nothing that I enjoy more than to think about science, to try to solve some scientific problen, to talk about science. If I were talking tonight about the nature of the chemical bond or the structure of proteins molecul or abnormal hemoglobin molecules in relation to disease I should be happy.

I am talking instead about science and freedom, about scientists in the present-day world of loyalty oaths, loyalty investigations, and passport restrictions because I feel that it is my duty to do so.

Let me first ask What is science! What is a scientist?

I answer that science is the search for the truth. A scientist strives to discover the truth about the world in which we live. He must be unhampered by dogma, he must not accept the idea of revealed truth.

This definition includes among scientists the social scientists, economists, historians, and other scholars who search for the truth. I shall, however, talk mainly about the physical and biological sciences.

We live in an age of science. Through scientific discoveries the world has been greatly changed from that of 150, 100, 50, even 25 years ago. Nuclear power plants and the hydrogen bomb were not dreamed of two decades ago.

How does a scientist make his discoveries? A popular idea is that he uses the scientific method of solving problems by logical, straightforward reasoning, by applying known principles. This way of making discoveries is used to some extent, but most discoveries are the results either of accident (plus keen observation and awareness) or of inspiration.

As examples of accidental discoveries I may mention penicillin by Fleming positron by Carl Anderson x-rays by Röntgen

Many, perhaps most, great discoveries, result from inspiration from new ideas, from flights of originality, even involving non sequiturs in reasoning. Examples: Newton, gravitation Einstein, theory of relativity Van `t Hoff, the tetrahedral carbon atom Kekulé, the cyclic structure of benzene

The significant new idea, the inspiration, is not easily found. I have tried to discover what the process is of having new ideas. With Poincaré, I feel that it is one of examination of millions of ideas and rejection of them, one after another, until a good one turns up, and that this process is carried out by the unconscious. I set the problem for the unconscious by thinking about it in bed, before going to sleep. Then a month or two later my unconscious may bring out an answer. Gauss, asked how he made his great contributions to mathematics, answered "By thinking about it all the time."

New ideas in science are hard to have because they are strange, unexpected. Heisenberg was willing to give up ordinary algebra and to invent a new algebra (new to him) in which ab is not equal to ba, in order to find a quantum mechanics of atoms. A conventional person would never have thought of taking such a radical step. Scientists must be radicals, not conservatives. They must feel free to examine any question from every point of view, to have every kind of idea; and this feeling must be a deep one, in the unconscious, or the unconscious will not solve the problem.

The European universities, over a period of centuries, discovered that scholars must be free. A simple argument explains why academic freedom was developed. A good professor is the man who knows more than anyone else in the world about his subject, and who has the best chance

of adding to it. No legislature, no board of regents, no university president can know as well as he how to work in this field and how to teach it — hence he, the professor, must be free to make the decisions, or the world will suffer.

We are now living through a period of attempted restriction of the freedom of scientists and scholars, attempts to control their thoughts, or at any rate to restrict the search for the truth and the open discussion of questions of great importance to mankind.

Restrictions of the freedom of scientists is not new. W. A. Tilden, discussing Italian science, said