Isaac Rabi was the first man who established radio contact with the magnetic properties of atomic nuclei, an achievement for which he received the Nobel Prize in Physics 1944. These properties had been discovered by Otto Stern (Nobel Prize in Physics 1943) and Walther Gerlach. Rabi showed that radio waves could force these magnetic nuclei to flip or change their orientation, releasing energy when they return back to their normal state – a phenomenon known as nuclear magnetic resonance. Besides X-ray crystallography, it turned out to be the most useful tool for identifying the structure of molecules and for imaging life. In Lindau, however, Rabi spoke only once about his work with „molecular beams“.
In addressing his young audience there, he was more interested in showing how science can help to maintain and build a peaceful world. This was no trivial task in the times of the Cold War, as Rabi vividly recalls from his own extensive experience in this lecture. Its basic theme is the capability of science to bring governments into closer interaction, and its quite optimistic assumption is that „international relations would be much simpler, if scientists were given the job and if they take the time to do it“.
Isaac Rabi was 41 years old when World War II broke out. He set up a laboratory in Cambridge, Massachusetts, devoted to radar research. He learned „to think about war in a military way“ and „to direct this laboratory in a direction, which would go for the purpose of winning the war“. He established many connections at different levels in the government and the military. This changed him, as he reports here. His scope widened and laboratory work alone did not suffice him any more. Most importantly, he witnessed the first test of an atomic bomb in Alamogordo on July 16, 1945. „I realized that people who had seen this, who had felt what it meant for the continuation of civilization...had to testify and do what they could to bring this under control in some form...I could not escape nor did I want to escape some kind of official semi-political involvement.“ Containing atomic weapons and promoting the peaceful use of nuclear energy became the main objectives of Rabi’s commitment for a better cooperation between nations.
He played, as he describes in this lecture, a leading role in organizing and conducting the United Nations’ International Conference on the Peaceful Uses of Atomic Energy, which took place in Geneva in August 1955 and lead to the foundation of the International Atomic Energy Agency two years later. Beyond that, he worked for the development of a world community of science wherever he could. As a member of the American delegation at a UNESCO conference in Florence in 1950, for example, Rabi, who had been among the founders of the Brookhaven National Laboratory, suggested to build a European particle accelerator. „This was an outrageous proposal at that time“, he says. „I had to convert myself to be a politician to try to persuade various delegations to support this.“ The result of this idea and efforts was the foundation of the CERN laboratory. Altogether, Rabi’s excellent knowledge, experience and networking, both in science and politics, gave him the reputation of a „statesman of science“, who was able to successfully realize many ventures in national and international cooperation. He was, as he says in this lecture, driven by the conviction that „science is not a profession, it’s not a technique, it’s much more than that, it’s a great discovery of the human spirit that it’s universal.“
 For a full account of this story, as related to Nobel Prizes of the 20th century, cf. http://www.nobelprize.org/educational/physics/imaginglife/.
 cf. Rigden, John S. Rabi, Scientist and Citizen. New York 1987.
 „The Conference was indeed a landmark in the history of science, the first intergovernmental conference ever held to illuminate progress on a new technology“, David Fischer writes on p. 31 of his book „The history of the International Atomic Energy Agency. The first forty years“, accessible on http://www-pub.iaea.org/MTCD/publications/PDF/Pub1032_web.pdf.
 Luisa Bonolis „Research Profile of Isidor Rabi“, http://www.mediatheque.lindau-nobel.org/#/RP?id=10888, p. 1.Joachim Pietzsch