Critical Thinking Media Competence

Confirmation Bias—Essay 1

The phrase “confirmation bias” describes a tendency for humans to think more about, and also favor, information that agrees to their own opinion whether the information is true or false.

Few months ago we operated an experiment by Peter Wason called “2-4-6” in class. Everybody had to guess the rule behind the sequence of the numbers 2-4-6. After some speculations it seemed, that a lot of people tried to test positives examples to confirm their own solution of the given rule. Almost no one tried to refute the rule or to find a wrong example to question their thoughts.

This specific mental activity of people was analyzed by Peter Wason. How stronger the emotionally issues are, the stronger is the effect of confirmation bias. The background of this thinking is, that humans rather confirm their existing opinion than question them. Nearly everybody is testing thoughts and ideas in the same way. Academics found out, that people focusing on the possibility and disregard other alternatives. A few academics follow the assumption of a connection between confirmation bias and wishful thoughts.


Confirmation bias is not only an interesting phenomenon in psychology but has also numerous consequences. People tend to be overconfident and ignore evidence. For example in stock markets can this effect lead to huge mistakes and in the past usually the investors who ignored it made the profit. But not only in finance is confirmation bias a problem. Also in politics and law is reasoning sometimes subconsciously biased and therefore conclusions that judges, juries or governments have already committed to are preferred. Therefore the inquisitorial and the adversarial criminal justice systems are affected by this topic.  Furthermore, it not only affects decision making but can be a factor in creating or extending conflicts. This can be a reason why an emotionally charged debate can be followed by war because each party can become overconfident.

Also science and scientific thinking is influenced by confirmation bias. Usually it is all about falsifying or confirming hypothesis or evidence. However, history states than many times scientists have ignored data which was not in favour of their theories. Studies have proven that everyone rates findings consistent with former beliefs as more important. This is something we can witness ourselves when we try to write an argumentative paper. Usually we have an opinion at the beginning and we have the same conclusion at the end. So we find more evidence that strengthens our beliefs ignoring the arguments which could change our mind.

There is even a profession beside psychology which makes money out of our desire to keep our beliefs. For instance psychic “readings” use this effect. Those “readers” are making a large number of statements to give us a large number of opportunities to find a match. So a psychic can deliver a reading without any prior information about the person.

These are just a few examples how confirmation bias effects everyday life and why it is so important for us to understand this phenomenon and why we should try to avoid it.

Further reasons

There a couple of reasons known, reinforcing people to be confirmation bias. The two most obvious determinants are time pressure and information overload. These two often go hand in hand. Closer examination of information can be difficult when there is either too much information or not enough time. Also the personality of a person can influence him/her on acting in a “confirmation bias” way. People who are very self-confident or need lot of self-affirmation can be more susceptible. These kind of people are more convinced of the correctness of an idea/thought/believe than other people might be.