Summary of Convocation Address, University of Missouri

Columbia, Missouri

29 November 1962

THE CULTURAL SIGNIFICANCE OF SCIENCE

by Linus Pauling

In speaking of the cultural significance of science I use the word cultural to mean pertaining to and conducive to culture, and the word culture to mean the intellectual content of civilization, the enlightenment and refinement of taste, conversance with and taste in the fine arts, humanities, and science, the understanding of the nature of the world in which we live, and the appreciation of its wonders.

During recent decades science has become a more and more important part of the world. Discoveries made by scientists have given us a far more penetrating and extensive understanding of the nature of the world, both inorganic and organic, then was had by our ancestors. Most of the significant new knowledge obtained year after year is now scientific. In order to be a cultured person, it is now necessary to have an understanding of science. I hope that each one of you students is spending some time on the study of science.

A knowledge of science is, of course, of great practical value in the modern world. But I believe that it is of still greater value in contributing to one's happiness, through the satisfaction of one's intellectual curiosity about the nature of the world. I hope that each one of you will continue with the study of science to such an extent as to enable you to read the articles in the Scientific American with appreciation.

Who is there who can fail to find pleasure in the discovery, made a few years ago, that the neutrino is not a simple elementary particle with zero rest-mass and zero electric charge, but instead has the extraordinary property of behaving like a little propeller -- and always like a right-handed propeller, with the anti-neutrino behaving like a left-handed propeller? Who is there who, knowing that at the present time it has been shown that there are two kinds of neutrinos, one related in some way to the electron and the other related in some way to the muon, is not full of curiosity about the nature of the difference between these two neutrinos?

Who is there who is not astonished that scientists have been able to discover that the source of energy in supernovae, those stars that suddenly flare into tremendous brightness and then die away, is the radioactive decay of the nuclide Californium 254? This discovery was made by scientists who noted that the supernovae decay to half their intensity in the period of 55 days; this period, 55 days, is the half-life of only one nuclide, Californium 254. Already in the year 1066 A.D. Chinese astronomers had noted that a great supernovae then flaming in the heavens decayed to half its intensity in 55 days; but nearly 900 years had to go by before science had developed to the extent where it was possible to explain this observed half life.

The molecular structure of the human body is now being investigated with great vigor. The nature of the molecules of DNA that carry the units of heredity, the genes, has now been discovered, and the way in which these molecules can manufacture duplicates of themselves is believed to be known. The molecular basis of some diseases, called molecular diseases, is now known. Some years ago it was discovered in our laboratory in Pasadena that patients with the serious disease sickle-cell anemia manufacture a kind of hemoglobin molecule that is slightly different from those hemoglobin molecules manufactured by other people. The difference amounts to only one part in 300 in the structure of the hemoglobin molecule; but even this small difference is enough to produce the serious manifestations of the disease.

Work on the amino-acid sequence of the polypeptide chains of hemoglobin molecules of different animals is leading to a greater understanding of evolution. The polypeptide chains of the hemoglobin molecules of the gorilla differ from those of humans by only one part in 146 in one chain and two parts in 141 in the second chain. The difference between the chains of horse and human amounts to about 18 parts in 141 or 146. With further study in this field it will become possible to discuss in a significant way the biochemistry of animals that lived 100 million or 500 million years ago.

The discoveries in the field of nuclear science have changed the nature of war. To appreciate how great the change has been we must make use of the methods of science, and in particular must discuss war in the quantitative manner characteristic of science.

People who are unaccustomed to making use of large numbers have difficulty understanding how many molecules of water there are in a glass of water, or how far away the stars are. They may also have the same difficulty in understanding the change that has taken place in the world during the last 17 years as a result of the development of nuclear weapons.

During the Second World War about 40 million people were killed. Three-tenths of one percent of the American people were killed in the war. In some other countries, however, the losses were 50 times as great -- about 15 percent of the people in some countries were killed. The Second World War was fought largely with ordinary explosives, with bombs such as the one-ton blockbuster, which might, when it exploded, kill 100 people. About three million tons of high explosive was used in bombs exploded during the Second World War. In modern nomenclature, the war was a three-megaton war.

The atomic bombs exploded at Hiroshima and Nagasaki had the explosive energy of 20,000 tons of TNT. They killed about 100,000 people apiece.

The present-day superbombs have explosive energy about a thousand times more powerful than the Hiroshima and Nagasaki atomic bombs. A 20-megaton superbomb has explosive energy seven times that of all the explosives used in the whole of the Second World War. One of these bombs exploded over New York would destroy it nearly completely, and might kill as many as 10 million people.

It is estimated that 2,000 megatons of bombs exploded over the United States would probably kill half of the American people, and 4,000 megatons exploded over the Soviet Union would kill half of the Russian people. 10,000 megatons exploded over the United States and 20,000 megatons exploded over the Soviet Union would kill or seriously injure all but a few million people, perhaps two million people, in each country.

The stockpile of nuclear weapons possessed by the United States is now estimated to be 200,000 megatons. This is 50 times the amount estimated to be needed to kill half of the Russian people, and ten times the amount needed to kill practically all of them. The stockpile of the Soviet Union can only be guessed at; it may be 50,000 megatons.

Possessing a larger stockpile of bombs than is necessary to kill everybody in an enemy country is described as having an overkill capability.

Only by thinking about these numbers can we reach a rational and sensible decision about the course which the world should follow. A part of the present-day cultural significance of science is that unless the people of the United States and the Soviet Union and of other nations attack the problem that the world now faces in a scientific and rational way, all culture may be destroyed in a nuclear war. I believe that the application of the discoveries made by scientists in the development of great nuclear weapons which, if used, could destroy civilization requires that war and the threat of war be abandoned as the instruments of national policy, and requires that we move toward a world governed by justice and international law and not by force. If this end is achieved, we may say that science has made the greatest of all possible contributions to culture. If it is not achieved, culture and civilization will no longer be found on earth.