One of the most frustrating exercises in human interaction can be arguing with someone who simply ignores or discounts any evidence that might contradict their opinion. It can be sobering to realize that we are all guilty of this faulty logic. We have a strong predisposition to what is called the Ubiquitous Confirmation Bias.The variation on the Watson Card Selection Task that follows is a wonderful illustration of this bias. Try it on yourself and share it with the loved ones you argue with the most: Each of the cards below has a letter on one side and a number on the other. Which two should be turned over to give you the most information on evaluating the following statement?
"If there is an S on one side, there is a 3 on the other"
CARDS
[S] [E] [1] [3]
Integrating the Contrary:
75% choose the S and 3. They believe that if the S has a 3 and the 3 has an S on their reverse sides, that this will confirm the statement "If there is an S on one side, there is a 3 on the other." 75% are wrong. While you must prove that "If there is an S on one side, there is a 3 on the other," you are not looking for any proof about what is on the other side of a 3. Therefore, what is on the reverse of the 3 gives us no meaningful information. Our predisposition is to prove the theory when we should be trying to disprove it. We should look at the other sides of the S (if there is any number other than 3 then the statement is false) and the 1 (if there is an S on the other side then the statement is false).
The Confirmation Bias is a particular problem when we start with a favored result we want to justify as we will underestimate our bias and overestimate it in others.
Living a life without any logical biases may be impossible, but acknowledging the bias may help us to be a little more humble.
Visit Sam Eaton"s Quantum Thoughts blog for more odd insights into our perception of the world.