July 17, 2017

429 Confirmation Bias [17 July 2017]


One of the sources for my column last week about saturated fat safety was an article by Gary Staube with the strange title “Vegetable oils, (Francis) Bacon, Bing Crosby, and the American Heart Association”. The article raised an issue I wanted to follow up on – bias in science.

Francis Bacon first articulated the problem of bias in 1620, nearly 400 years ago:
The human understanding, once it has adopted opinions…draws everything else to support and agree with them. And though it may meet a greater number and weight of contrary instances, it will, with great and harmful prejudice, ignore or condemn or exclude them by introducing some distinction, in order that the authority of those earlier assumptions may remain intact and unharmed.

The Bing Crosby connection is the lyrics to his hit song “Accentuate the positive, Eliminate the negative…” which is what we do when sifting information about an issue on which we have a position. It is what lawyers do when arguing for their client in court, but not what scientists should be doing in seeking the truth. And what, Staube argues, the American Heart Association did in selecting the studies to support their now outdated position on saturated fat and heart disease.

Elizabeth Kolbert in a February 2017 article in The New Yorker “Why facts don’t change our minds” describes modern psychological experiments which support what is called “confirmation bias”. We readily believe information that agrees with our thinking and disregard anything to the contrary, spotting weaknesses in our opponents’ arguments but not in our own. Furthermore even when we realize that what we thought is not true we are unable to effectively reverse our first impression.

A classic Peanuts cartoon strip illustrates this perfectly: Lucy and Linus see something on the sidewalk and Lucy says “Look a big yellow butterfly…they fly up from Brazil and they…” Linus interrupts to point out that it’s a potato chip not a butterfly. Lucy looks closer and then exclaims “So it is! I wonder how a potato chip got all the way up here from Brazil?”

Confirmation bias has polarized almost every issue in politics, religion, and health science (and many more). At least part of the solution is to recognize this bias – in ourselves as well as others – and critically examine both sides of issues.

For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.

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