A forty-year old psychology experiment reveals why we should be careful about what we think we know.

Name of concept: Confirmation Bias.

Where did it come from: Psychology, philosophy of science.

Who came up with it: Peter Wason.

What it is about: Human beings are easy to fool. Almost all of us select information that confirms what we think we know, and downplay or ignore information that conflicts with our beliefs. People often remark how extraordinary it is that someone telephones them just as they were thinking about that person, but forget all the times when the telephone did not ring. Scientists call this confirmation bias.

Again, unwise political leaders tend to make decisions by selecting information that supports their beliefs and ignoring data that does not. It seems clear that many of those that decided to go to war in Iraq were victims of this syndrome. The US . . .  read »