Tuesday, May 20, 2014

Why people don't believe what the evidence indicates to be true

There is an interesting New Yorker article that deals with the persistence of false beliefs. I am going to do violence to the article's thesis, but my take on it is as follows:
Take a proposition A. If you feel that you are the kind of person who believes proposition A, it will be hard to get you to believe proposition A is not true by citing evidence or emotional appeals to the dangers of acting in accord with belief in proposition A. If proposition A is simply a value free statement, the belief can easily be changed.
So a statement such as "Malaria was a significant cause of illness in Michigan during the summers in the early 19th century" might be thought to be false, but that belief might be easily changed by reading a historical account stating it to be true.

On the other hand, if you understand yourself to be a strong partisan of your political party, and if you feel that a certain position on climate change is a fundamental tenet of your party,  it may be very hard to get you to change your position on the reality of climate change. Republicans tend to deny human action is causing global warming, but may freely acknowledge that many scientists publicly endorse that belief.

If you feel that your religious affiliation is a fundamental element of your personal identity, and if you feel that a tenet of your religion is the literal truth of the biblical creation story, it may be very difficult to get you to believe in the "big bang theory" and evolution. Indeed, educated Christian fundamentalists will often report that scientists strongly support the big bang theory and the theory of evolution,  but they themselves -- the Christian fundamentalists -- do not believe them.

This is a very different situation that scientific skepticism. Scientists should demand evidence supporting a proposition before they give it credence. They should demand replication of experiments to assure that specific experimental results are neither the result of experimental error of statistical anomaly.

So too, scientists should retain skepticism of even well supported theories. Thus, scientists should be willing to reject a long held theory if a better one comes along. Even Newton's theory was replaced by Einstein's after hundreds of years of evidence supported Newton. Einstein's theory provided predictions consistent with Newton's in most circumstances, but Einstein suggested experiments that would distinguish between the two theories and his theory's prediction proved more accurate for those instances.

No comments: