On Confirmation Bias

19 January, 2022 - 8 min read

The tendency of the human brain to filter out information that contradicts its existing beliefs.


A confirmation bias makes people look for information that is consistent with what they already think, want, or feel, leading them to avoid, dismiss, or forget information that will require them to change their minds and behavior.

When we have pre-existing beliefs, we often take facts and make them fit with these beliefs. Facts are interpreted selectively. We like to agree with the facts which support our beliefs and throw out or misinterpret the ones we don't agree with.

In short, we see the world as we want to see it, not as it is.

Deep analysis

Confirmation bias clouds our judgment. It gives us a skewed view of information, even when it consists only of numerical figures. We know how confirmation bias gets in the way of thinking clearly. So why do we carry this bias?

Accepting information that confirms our beliefs is easy and requires little mental energy. Seeking out an objective statistical rigor is challenging because our laziness prevents us from updating our thinking.

But failing to interpret information in an unbiased way can lead to serious misjudgments. It can create bad habit patterns. Research has shown that when you recall episodic memory, you will fill in information using confirmation bias, thus enforcing your memory to recall only what you believe in and refute the ones that you don't believe in.

Wikipedia has a great take on confirmation bias:

It is an important type of cognitive bias that has a significant effect on the proper functioning of society by distorting evidence-based decision-making. People display this bias when they gather or remember information selectively, or when they interpret it in a biased way. The effect is strongest for desired outcomes, for emotionally charged issues, and for deeply entrenched beliefs. People also tend to interpret ambiguous evidence as supporting their existing position. — Wikipedia

Darwin on prejudice

In any good scientific experiments, researchers should seek to falsify their hypotheses, not to confirm them.

Darwin knew this really well and was determined to avoid prejudice. Darwin goes through remarkable lengths to prevent what psychologists call “confirmation bias” and other forms of psychological misjudgment that would deteriorate his work. He undoubtedly realized that he can fool himself subconsciously, and put in place various habits to keep prejudice in check.

I have steadily endeavoured to keep my mind free so as to give up any hypothesis, however much beloved (and I cannot resist forming one on every subject), as soon as facts are shown to be opposed to it. Indeed, I have had no choice but to act in this manner, for with the exception of the Coral Reefs, I cannot remember a single first-formed hypothesis which had not after a time to be given up or greatly modified. — Charles Darwin

Even when Darwin began to appreciate the formation of new species, a theory that had been a mystery to him for years, he was anxious to work on it so as to avoid any prejudice.

The result of this would be the formation of new species. Here then I had at last got a theory by which to work; but I was so anxious to avoid prejudice, that I determined not for some time to write even the briefest sketch of it. — Charles Darwin

Our natural inclination is to cling to our beliefs, particularly if we are reinforced by recent experiences–a flaw within our makeup. Darwin was good at realizing this flaw. If all scientists do a better job of addressing their confirmation bias, we could save a huge amount of time and money.

Not everyone is Darwin, so we must remember not to take science at face value because the reporting could be biased due to confirmation bias.

Kill the belief bubble

Practice stress testing your beliefs. Try having a non-emotional discussion or debate with that person and see how they came up with their belief. This could be any topic such as religious, political, or parenting. Then see how your beliefs are different than the person you are discussing this topic with.

  • Pick something from your list to stress test on. Be honest with yourself while conducting this exercise. Remember why you are doing it in the first place.
  • Conduct research and list all the opposing viewpoints for your beliefs. Try to see things from this perspective while staying objective. Compare them how they differ from your existing beliefs.
  • Once you think you have a grasp of all sides of the issue. What did you learn that will kill or keep your existing beliefs? Can your new beliefs be validated? If so, how can it be objectively validated?

Even if you were right all along, it is worth conducting this exercise to stress test your ideas. The more rigor you apply, the better informed you will be. This is where growth lies.

Confirmation bias & self-confidence

Many people deny that they are affected by confirmation bias. After all, most of us see ourselves as intelligent and rational people. But we don't give enough credit to our emotional state. Not understanding this can create cognitive dissonance which we mistake it for self-confidence.

We are bombarded by information. It comes from other people, the media, our experience, and various other sources. Our minds must find means of encoding, storing, and retrieving the data we are exposed to.

One way we do this is by developing cognitive shortcuts and models. These can be either useful or unhelpful. Constantly evaluating our worldview is exhausting, so we prefer to strengthen it instead. Plus holding different ideas in our head is hard work. It’s much easier to just focus on one and create wrong models in our head leading to over-confidence.

A very difficult journey to embark on, but we must at least strive to fight for our confirmation biases.


Man is not a rational animal, he is a rationalizing animal. — Robert Heinlein

As a man wants, so shall he believe. — Greek Philosopher

The eye sees only what the mind is prepared to comprehend. — Robertson Davies

One of the biggest problems with the world today is that we have large groups of people who will accept whatever they hear on the grapevine, just because it suits their worldview—not because it is actually true or because they have evidence to support it. — Neil deGrasse Tyson

The most difficult subjects can be explained to the most slow-witted man if he has not formed any idea of them already; but the simplest thing cannot be made clear to the most intelligent man if he is firmly persuaded that he knows already, without a shadow of doubt, what is laid before him. — Leo Tolstoy

Beliefs can survive potent logical or empirical challenges. They can survive and even be bolstered by evidence that most uncommitted observers would agree logically demands some weakening of such beliefs. They can even survive the destruction of their original evidential bases. — Lee Ross and Craig Anderson

The confirmation bias is so fundamental to your development and your reality that you might not even realize it is happening. We look for evidence that supports our beliefs and opinions about the world but excludes those that run contrary to our own… In an attempt to simplify the world and make it conform to our expectations, we have been blessed with the gift of cognitive biases. — Sia Mohajer

The human understanding when it has once adopted an opinion, draws all things else to support and agree with it. And though there be a greater number and weight of instances to be found on the other side, yet these it either neglects and despises, or else by some distinction sets aside and rejects. — Francis Bacon

The desire to be right and the desire to have been right are two desires, and the sooner we separate them the better off we are. The desire to be right is the thirst for truth. On all counts, both practical and theoretical, there is nothing but good to be said for it. The desire to have been right, on the other hand, is the pride that goeth before a fall. It stands in the way of our seeing we were wrong, and thus blocks the progress of our knowledge. —  Willard V. Quine and J.S. Ullian

When you forget that people and ideas are separate, your entire thinking process is laden with a crippling burden: to protect your beliefs like you protect your body. —  Tim Urban

The number one thing that clouds us from being able to see reality is that we have preconceived notions of the way it should be. — Naval Ravikant

What the human being is best at doing is interpreting all new information so that their prior conclusions remain intact. — Warren Buffett