Linus Pauling (1901—1994) was one of the first scientists to work in the fields of molecular biology and quantum mechanics and is considered to be one of the greatest scientists of all time, before his unfortunate late turn to pseudoscience.
 Scientific work
 The good
He had already won awards for his work in quantum theory before he had even turned thirty. His work defining sickle cell anemia as a molecular disease opened up many new paths of research. In the 1950s, he argued that DNA had a triple helix structure as opposed to Watson and Crick's double helix model, but then revised his position after he got access to Watson and Crick's higher quality X-ray diffraction photos. He won the 1954 Nobel Prize in Chemistry for his seminal work on chemical bonds, which is summarized in his book The Nature of the Chemical Bond. He also won the Nobel Peace Prize for his anti-war activism.
 The not so good
In his later days, he sank into Vitamin C crankery, claiming that megadoses of the vitamin could cure the common cold. This eventually led to a field of quackery known as orthomolecular medicine, which goes to show that even the most brilliant person can also fall for pseudoscience sometimes. He and Arthur Robinson set up an institute in Pauling's name to promote this quackery.
 Political activities
In the aftermath of World War Two, Pauling and his wife became pacifists, joining the Emergency Committee of Atomic Scientists. His political activism resulted in the State Department denying him a passport until Senator Wayne Morse denounced the action publically.
All this meant that he was a perfect target for Red baiting. He was ordered to appear before the Senate Internal Security Subcommittee where he was accused of "the number one scientific name in virtually every major activity of the Communist peace offensive in this country"
 See Also
- Bio at the Pauling Institute
- Bio at the National Academies
- Oregon State University's archive of Pauling material
- The Dark Side of the Pauling Legacy, Quackwatch