Linus Carl Pauling was born in Portland, Oregon, USA, on February 28, 1901.

Linus Pauling started reading a lot as a child and after seeing some chemical experiments made by a friend he decided he would become a chemist. Also thanks to his attitude to studying he was admitted to Oregon State University when he was just 16.

His father died in 1910 so Linus Pauling had to work for the university in the classroom and laboratory to pay for his education. In 1922 he graduated in chemical engineering and continued his studies at Caltech in Pasadena, where he earned a Ph.D. in physical chemistry and mathematical physics in 1925.

At the university, Linus Pauling met Ava Helen Miller, who became his wife: together they had four children.

During his career, Linus Pauling devoted himself to quantum chemistry applying quantum physics in determining the structure of molecules and the nature of the bonds. Among his findings there’s the concept of chemical affinity, he also compiled the best known among the scales of electronegativity.

Linus Pauling’s research also affects biochemistry: in particular, his studies on hemoglobin were important also to understand the nature of diseases such as sickle cell anemia. Francis Crick, one of the discoverers of DNA, recognizes Pauling as the father of molecular biology.

In 1954, Linus Pauling received the Nobel Prize for Chemistry for his research on the nature of chemical bonds and for his research in understanding the structure of complex substances.

Linus Pauling is also remembered for his peace activism. In 1946 he joined the Emergency Committee of Atomic Scientists led by Albert Einstein, whose goal was to raise awareness about the dangers of nuclear proliferation.

Those were the dark years of McCarthyism and positions that weren’t overtly patriotic drew criticism. The nicer ones accused him of naivety but there were those who accused him of being an accomplice to the Communists. In 1952 he was denied the passport, which was returned only after two years.

In 1955 Linus Pauling, along with Einstein, Bertrand Russell, and other scientists signed the Russell-Einstein Manifesto. In 1958 Pauling joined an initiative that led to a research that showed the risk that nuclear testing surface caused to public health due to contamination of land and life forms invested by the fall of radioactive elements.

Linus Pauling and his wife presented the United Nations with a petition signed by more than eleven thousand scientists who called for the suspension of nuclear tests which in 1963 led to an international moratorium on surface tests. For this reason, Pauling was awarded the Nobel Peace Prize.

Linus Pauling continued his activism in various ways: in 1974 he was among the founders of the International League of humanists and he was president of the scientific committee of the World Union for Protection of Life. Over the years he got closer and closer to the position of humanism and in the last years of his life, he openly declared as an atheist.

Linus Pauling died on August 19, 1994, due to prostate cancer.

Recently within the U.S. government, someone somehow made amends for the way Linus Pauling had been treated. For example, the U.S. Postal in 2008 issued a stamp in his honor and California Governor Arnold Schwarzenegger introduced him to the California Hall of Fame at the California Museum for History, Women and the Arts.

Times have really changed since the Cold War so after his death, Linus Pauling was added to the list of the twenty greatest scientists of all time by the New Scientist magazine, which described him as one of the greatest thinkers and visionaries of the millennium. Pauling undoubtedly influenced subsequent generations of chemists and biologists, and his activism has helped to make the world a little less dangerous with a vision of peace we still need.