What Is Confirmation Bias?

Post Author: Bill Pratt 

Confirmation bias is a concept you need to understand because it impacts all of us, and we are mostly unaware.

Psychologist Daniel Kahneman, in his book Thinking, Fast and Slow, describes confirmation bias in the context of a person being presented with a statement that they can choose to believe or not believe. Kahneman begins, “The initial attempt to believe is an automatic operation of System 1 , which involves the construction of the best possible interpretation of the situation. Even a nonsensical statement . . . will evoke initial belief.” (emphasis added)

Kahneman explains that unbelieving is an operation of System 2, but we already know that System 2 requires additional cognitive energy to get engaged. So what does this mean?

The moral is significant: when System 2 is otherwise engaged, we will believe almost anything . System 1 is gullible and biased to believe, System 2 is in charge of doubting and unbelieving, but System 2 is sometimes busy, and often lazy. Indeed, there is evidence that people are more likely to be influenced by empty persuasive messages, such as commercials, when they are tired and depleted.

And now comes the concept of confirmation bias:

The operations of [System 1] associative memory contribute to a general confirmation bias. When asked, “Is Sam friendly?” different instances of Sam’s behavior will come to mind than would if you had been asked “Is Sam unfriendly?” A deliberate search for confirming evidence, known as positive test strategy, is also how System 2 tests a hypothesis.

Contrary to the rules of philosophers of science, who advise testing hypotheses by trying to refute them, people (and scientists, quite often) seek data that are likely to be compatible with the beliefs they currently hold. The confirmatory bias of System 1 favors uncritical acceptance of suggestions and exaggeration of the likelihood of extreme and improbable events.

Unless we are paying close attention and engaging System 2, our bias is to believe what we are told. System 1 will pull memories and ideas out of our mind to confirm whatever is being presented to us. It is only when we pause, think, and consider what is being said, that System 2 can start to methodically test what is being presented to us.

As someone who reads a tremendous amount of anti-Christian material, I am aware of this process happening to me all the time. I will read statements that say, in effect, “This aspect of the Christian worldview is totally wrong,” and my initial reaction, if I don’t have my mind really engaged, is almost always to agree! In fact, if I just uncritically read any author, I will find myself wanting to agree with most of what the author is saying.

I don’t think this reaction is all bad, though. The best way to understand another person’s viewpoint is to immerse yourself in their ideas as best you can, and try to see the world as they see it. If you stop to critically analyze every sentence, you will quickly exhaust yourself and never see as the other person sees.

So my recommendation is to let System 1 have its way when you are reading new material, at least for a while. Once you’ve uncritically read enough to understand the main point of the author, then go back and bring System 2 into the game. Analyze, critique, question what you’ve read.

The situation where System 1 can really be dangerous for a person is when that person only reads material that already confirms their previous beliefs, and reads without ever engaging System 2 to analyze, critique, and question what they’ve read. If this happens over and over again for years, you have the making of a dogmatic and stubborn individual, someone who is rarely thinking about what they believe.