Linus Pauling was passionately interested in the natural world. Everything he could see, touch, or imagine, from stars to subatomic particles, crystals to cognitive processes, had the power to fascinate him. By the time he was just 32 years old, in 1933, his combination of deep knowledge and theoretical acumen had already made him an internationally renowned chemist. He ran one of the world's most productive chemical laboratories from his academic home base at the California Institute of Technology (Caltech). Almost all of his work centered on the nature of the chemical bond and the structure of minerals and inorganic molecules.

But his mind ranged beyond that, to topics from physics to medicine. Like all scientists, he also needed money to support his work. But Pauling's need was greater than most. His work required some of the most complex and expensive machines of the day. He was an expert at using x-ray crystallography equipment, for instance, which was not only costly and difficult to run, but required a dedicated staff of "human computers" to help interpret the results. Pauling, more than most chemists, needed significant funding from outside his institution.

Research dollars were not easy to find during the Great Depression. Pauling, however, had the patronage of the Rockefeller Foundation (RF), at that time the world's most important source of money for science. Pauling developed a close relationship with the head of RF's natural sciences division, the owlish scientific talent scout Warren Weaver. Weaver was a visionary. In the early 1930s he was especially enthused about what he saw as a coming revolution in biology. The "old" biology – the study of plants and animals at the level of the whole organism – was going to be transformed, he believed, by the application of techniques and approaches from the "hard" sciences: mathematics, physics, and chemistry. The new biology would bore into the workings inside the body, at the level of molecules. Weaver intended to spur what he called "the friendly invasion of the biological sciences by the physical sciences."

After searching the world for the most talented revolutionaries, Weaver decided that Linus Pauling was the right man to lead the charge.