Powerful pull of belief

Research on confirmation bias has found that when subjects are presented with evidence that contradicts their deeply held beliefs, they dismiss it as invalid, while other subjects treat the same information as valuable when it confirms what they believe. In one study, for example, subjects were shown a video of a child taking a test. One group was told that the child was from a high socioeconomic class; the other group was told that the child was from a low socioeconomic class. The subjects were asked to evaluate the academic abilities of the child based on the results of the test. The child believed to be from the high socioeconomic group was rated as above grade level, but the child believed to be from the low socioeconomic group was rated as below grade level. Same data. Same kid. Different interpretations.

The confirmation bias sways us all, especially when it reinforces our inner tribalism. Most of us will never join a cult, but all of us are subject to the pull of believing that the evidence supports our most cherished beliefs. Inside Jonestown, Jim Jones' daily barrages confirmed to members that their cause was right and that ultimately death would bring about peace and justice.

It is for this reason that we need to look for disconfirmatory evidence, to listen to the arguments of those with whom we disagree, to ask for constructive criticism of our beliefs, and to remember Oliver Cromwell's words to the Church of Scotland in 1650: "I beseech you, in the bowels of Christ, think it possible you may be mistaken."