Some beliefs are merely a product of the times, or big ideas that didn't pan out, others are not, but the bottom line is that scientists are not all-knowing. Expertise in one area doesn't mean expertise in all others. Here are some other examples of scientists gone astray (and all but one of them has won the Nobel prize) - and why we shouldn't take every word as truth without some critical thinking.
James Watson - The inspiration for this post requires little description, as his recent comments about African intelligence have been discussed both on this blog and throughout the blogosphere. This isn't the first time Watson has stirred controversy with his remarks. He has come under fire for comments about homosexuality, women in science, eugenics and previous racially charged remarks.
William Shockley - Another Nobel prize winner, this time for physics (1956). Shockley was concerned about a 'dysgenic' effect in the population and, like Watson, made several comments about the intelligence of people of other races. His thoughts about eugenics - he once proposed that people with below average intelligence should be paid to undergo voluntary sterilizaion - and his racist views left him ostracized by his friends and family, and his scientific accomplishments tarnished.
Sir Isaac Newton - Inventor of calculus. Father of classical mechanics. Alchemist? In between his theory of gravity and the publication of Principia Mathematica, Newton sought the fabled Philosopher's Stone despite the heavy penalties for practicing alchemy at the time. His quest to turn lead into gold was never published, but was rediscovered when John Maynard Keyes bought many of Newton's unpublished works at auction and, after learning their contents, proclaimed that "Newton was not the first of the age of reason, he was the last of the magicians." Newton's study of alchemy might be explained as an offshoot of his scientific study at a time when science and alchemy were intertwined, but his odd pursuits also extended to bibilical prophecy - including predictions about the end of the world.
Kary Mullis - The acid-dropping, surfing, Nobel prize winner, unsurprisingly, has his own share of controversial ideas. The inventor of PCR has been associated with Peter Duesberg in the past and has been highly skeptical of the HIV-AIDS link - making him a poster child for the HIV denialist movement. Mullis is also skeptical of man-made global warming and disagrees with the idea that CFCs cause ozone depletion. All of these views go against mainstream scientific consensus. On top of that, he's a firm believer in astrology and even devotes a chunk of his autobiography, Dancing Naked in the Mind Field, to its validity. Oh, and he's had a possible alien encounter with a speaking, glowing, raccoon-like creature.
Linus Pauling - Pauling has the distinction of being the only person to win 2 unshared Nobel Prizes as a brilliant scientist (Chemistry, 1954) and an anti-war advocate (Peace, 1962). Pauling is also responsible, in part, for the widespread belief that megadoses of vitamin C is an effective cold remedy - a claim that hasn't stood up to scientific scrutiny (doses up to 250mg may reduce symptom severity, but beyond that no benefits were observed). Pauling's views on 'orthomolecular medicine', as he dubbed it, is reminiscent of the quackery we discuss on the Bayblab from time to time: any noticeable changes were attributed to Vitamin C, while ineffectiveness was chalked up to 'too low a dose'. And the illness cured by his high vitamin doses also expanded - from curing the common cold, then curing cancer and finally to "improve your general health . . . to increase your enjoyment of life and can help in controlling heart disease, cancer, and other diseases and in slowing down the process of aging."
The point here isn't to downplay the accomplishments of otherwise brilliant men or run some sort of smear campaign. We need to remember that nobody is an expert on everything and anyone can make mistakes - we need to think and evaluate for ourselves. Quackery or racism shouldn't be tolerated from anyone but if Watson wants to chat with me about DNA structure or Mullis about PCR I'm willing to listen.