Cognitive Biases: What They Are and How They Affect You

Cognitive Biases


A cognitive bias is a systematic pattern of deviation from rationality, which occurs due to the way our cognitive system works. Accordingly, cognitive biases cause us to be irrational in the way we search for, evaluate, interpret, judge, use, and remember information, as well as in the way we make decisions.

For example, one well-known cognitive bias is the illusion of transparency, which causes us to believe that our thoughts and emotions are more apparent to others than is actually the case. We experience this bias because when we try to imagine how others see us, we struggle to properly shift away from our own internal perspective.

Cognitive biases affect our thought process in every area of life, from how we form our memories, to how we shape our beliefs, and to how we connect with other people. The patterns of irrationality that represent the various cognitive biases vary in terms of how they affect us and in terms of their scope. Accordingly, cognitive biases can lead to minor issues, such as forgetting a small detail from a past event, or they can lead to more serious issues, such as choosing to reject life-saving treatment due to a misguided belief in a pseudoscientific course of treatment.

Because cognitive biases have such a pervasive influence, it’s important to understand them. In the following article, you will learn more about cognitive biases, understand why they affect us, see what types of them exist, and find out what you can do in order to mitigate them successfully.


Examples of cognitive biases

One example of a well-known cognitive bias is the halo effect, which is a cognitive bias that causes our impression of someone in one area to influence our opinion of that person in other areas. This means that, for example, if we think that someone is physically attractive, we tend to believe that they are also more knowledgeable and have a better personality compared to what we would think if they were unattractive.

Another example of a cognitive bias is the illusion of control, which is a cognitive bias that causes us to overestimate our ability to control the outcome of situations where chance plays a greater role than skill. This means that, for example, this bias could cause us to undertake a risky business venture, even if that venture is likely to fail regardless of how much effort we put into it.

Overall, cognitive biases can affect us in many areas of life, from how we interpret new information, to how we remember past events, and to how we perceive other people. The two biases listed here represent two simple examples of cognitive biases, and throughout the article, you will see examples of various other biases that affect us.


Who experiences cognitive biases

Cognitive biases are generally viewed as a shared universal trait that all humans experience. This is because biases occur due to the way that our basic cognitive system works, meaning that anyone can experience cognitive biases, including entrepreneursmedical doctors, and even psychologists.

Furthermore, cognitive biases have been observed not only in humans but also in animals, such as bees, pigs, and dogs. However, the type of biases that these animals experience varies significantly across species, due to the innate differences in cognitive functions.

It’s important to note that various background factors, such as age, personality type, and general cognitive ability, can make people more predisposed to certain cognitive biases. However, the relationship between these background factors and the occurrence of cognitive biases is highly complex, and every person experiences some cognitive biases, to some degree.


Why we have cognitive biases

In short, cognitive biases are caused by the imperfect way in which we process information and make decisions, and primarily as a result of our tendency to use mental shortcuts that allow us to think faster but also make us more likely to make mistakes.

To understand why we have cognitive biases, it’s important to first understand the concept of bounded rationality, which is the idea that our decision-making ability is constrained by the limitations of our cognitive systems, and depends on the type of information that we have to process as well as on the amount of time that we have in order to process it. This means that when we try to solve a problem, we often end up reaching a solution that is different from the one we would reach if our cognitive systems were perfect, or from the one that we would reach if we had more time to consider the problem.

Under this framework, people are seen as being bounded rationally and as satisficing. This means that we make decisions that are not necessarily optimal, since instead of looking for the best solution that is available for a certain problem, we generally tend to look for a solution that is perceived as good enough given the circumstances.

A common way in which we do this is by using heuristics, which are mental shortcuts that help us quickly reach a ‘good enough’ solution to our problems. For example, if we are asked how many apples there are in a certain basket, then instead of counting each apple individually, we might decide to estimate this amount by counting the number of apples in one section of the basket, and then multiplying that amount by the number of sections.

Overall, this means that cognitive biases occur when we a select sub-optimal solution to a problem, due to the way that our cognitive systems work. There are two main cognitive systems at play here:

  • System 1. This cognitive system is responsible for our intuitive processing. It is fast, automatic, and effortless. Accordingly, processes on this system run in parallel, meaning that it’s possible to engage this system on multiple fronts simultaneously. This system can be strongly influenced by emotional considerations. An example of a situation where this system is engaged is when we feel pleased because someone laughed at a joke that we told.
  • System 2. This cognitive system is responsible for our conscious reasoning. It is slow, controlled, and effortful. Accordingly, processes in this system run in a serial way, meaning that this system can only focus on one thing at a time. This system is emotionally neutral, and therefore is not influenced by emotional considerations. An example of a situation where this system is engaged is when we try to solve a complex math problem in our head.

Based on this, one way in which the use of our cognitive systems can cause us to experience a cognitive bias is when we rely on our intuition (System 1) in order to make a decision that normally requires complex reasoning skills (System 2).

For example, in one experiment, students at Princeton University were asked a simple brain teaser:

“A bat and a ball cost $1.10 in total. The bat costs $1 more than the ball. How much does the ball cost?”

Almost anyone who hears this question feels an initial tendency to answer “10 cents”, because the total sum of $1.10 separates naturally into $1 and 10 cents, so that that the answer “10 cents” sounds about right in terms of magnitude.

The problem is that over half the people in the experiment ended up sticking with this initial estimate, leading them to answer this question incorrectly, since the right answer is that the bat costs $1.05, while the ball costs $0.05.

Essentially, what happens here is that most people make an intuitive assessment of the situation using System 1, which gives them a close but incorrect answer to the question.

Some people then use System 2 in order to reassess this initial solution, which allows them to realize that it’s incorrect, and which consequently leads them to calculate the correct solution to this question. However, other people fail to engage System 2 properly or at all, which means that they end up relying on the incorrect initial assessment that they got from System 1.

Of course, this does not mean that the intuitive assessments provided by System 1 are inherently faulty. Rather, our intuition can be a powerful and accurate tool, and there are many situations where our intuition provides us with the right solution to problems that we encounter. Instead, the issue here is that our intuitive system (System 1) usually requires monitoring by our conscious reasoning system (System 2), in order to identify and correct any errors that occur due to faulty intuitions.

Overall, based on this framework, cognitive biases occur primarily due to a failure of three cognitive mechanisms:

  • Failure of System 1 to generate a correct intuitive impression. This means that System 1 gives us a quick but incorrect solution to our problem.
  • Failure of System 2 to monitor impressions generated by System 1. This means that System 2 fails to notice and correct faulty impressions which are generated by System 1.
  • Failure of System 2 to reason correctly. This means that System 2 gives us an incorrect solution to our problem, due to a failure of our conscious reasoning process.

Note that which system is engaged in which task depends on a person’s skill level, and on the circumstances under which they perform the task in question.

For example, skilled drivers are generally able to talk while driving, which indicates that for them, driving is intuitive, since it’s difficult to perform two System 2 processes simultaneously, as we saw above. However, even the most experienced drivers will generally struggle to talk if they’re driving in rough conditions, which require their full attention.


Types of cognitive biases

There are two main criteria that you can use in order to categorize the different types of cognitive biases:

  • Area of cognition. Different biases affect different domains of our thinking. For example, some biases affect the way we recall information, while other biases affect our perception of ourself, and yet other biases affect our decision-making process.
  • Cause of bias. Different biases occur due to different reasons. For example, some biases occur due to our brain’s limited information-storing capacity, while other biases occur due to our attempts to feel good about our decisions, and yet other biases occur due to our susceptibility to social pressure.

Note that earlier, we saw that cognitive biases occur due to the failure of System 1 and System 2 to function properly. However, when it comes to categorizing cognitive biases, ’cause of bias’ more frequently refers to the overall mechanism underlying the bias. This is due to the fact that this type of categorization more accurately captures the nature of the different cognitive biases, and due to the variation in terms of which System people use in order to run which cognitive processes.

Next, we will see examples of the different types of cognitive biases, based on the area of cognition where the bias occurs, and based on the cause of the bias.


Area of cognition

Different biases affect different areas of our cognition. Based on this criterion, some of the most common types of biases include:

  • Information biases. These are biases that affect the way in which we acquire and process information. For example, the overkill backfire effect is a cognitive bias that causes people who encounter a complex explanation to reject it in favor of a simpler alternative. This occurs because people generally prefer information that is easy for them to process from a cognitive perspective.
  • Belief biases. These are biases that affect the way in which we form and modify our beliefs. For example, the worldview backfire effect is a cognitive bias that causes people to strengthen their support of their preexisting beliefs, when they encounter evidence that shows that those beliefs are wrong. This occurs because when people argue strongly against unwelcome information, they end up with more arguments that support their original stance.
  • Decision-making biases. These are biases that affect the way we make decisions. For example, the bandwagon effect is a cognitive bias that causes people to do something because they believe that other people are doing the same thing. This occurs because people feel a need to conform and act in accordance with others, and because people often rely on other people’s judgment when deciding how to act.
  • Calculation biases. These are biases that affect the way in which we calculate things such as probabilities or values. For example, the gambler’s fallacy is a cognitive bias that causes people to mistakenly believe that if something happens more frequently than normal during a given time period, then it will happen less frequently in the future. This occurs because people believe that a short sequence of random independent events should be representative of a longer sequence of such events.
  • Memory biases. These are biases that affect the way our memory works. For example, rosy retrospection is a cognitive bias that causes people to remember past events as being more positive than they were in reality. This occurs because when people experience a certain event, they tend to have both positive and negative thoughts, but as time passes they are more likely to forget their negative thoughts than their positive ones.
  • Social biases. These are biases that affect our social perception and behavior. For example, the spotlight effect is a cognitive bias that causes people to think that they are being observed and noticed by others more than they actually are. This occurs because people naturally see everything from their own point of view, so they struggle to accurately judge how they look through other people’s eyes.

Note that many of these areas of cognition are interrelated, meaning that some biases can affect our cognition in several domains. For example, the bandwagon effect, which as we saw above causes people to conform to the attitudes of others, affects not only the way we make decisions, but also the way in which we form our beliefs, and the way in which we shape our social behavior.

Another bias that can affect several areas of our cognition is the confirmation bias, which is a cognitive bias that causes people to search for, favor, interpret, and recall information in a way that confirms their preexisting beliefs. This bias can, for example, affect the way we acquire new information, as well as the way we remember old information, and the way we evaluate different choices.


Cause of bias

Biases can occur due to various reasons, with the most common causes being:

  • Heuristics. These are biases that are caused by our use of mental shortcuts. For example, the representativeness heuristic is a heuristic that causes people to focus on how representative someone or something is of a particular class, when assessing the likelihood that they belong to that class. This occurs because focusing on representativeness allows people to quickly assess the situation and reach a roughly correct conclusion in many cases, without them having to deal with complex background information.
  • Limited cognitive capacity. These are biases that are caused by our limited cognitive capacity. For example, the Google effect is a cognitive bias that causes people to forget information that they believe can be easily found online. This occurs because people sometimes prefer to rely on their ability to remember how to find information, rather than on their ability to remember the information itself.
  • Noisy information processing. These are biases that are caused by the effects of various background factors on the way we process information. For example, the humor effect is a cognitive bias that causes people to remember information better when that information is perceived as humorous. This occurs because humorous information benefits from increased attention and improved encoding, compared to non-humorous information.
  • Emotional motivation. These are biases that are caused by various emotional considerations. For example, the ben franklin effect is a cognitive bias that causes people to like someone more after they do that person a favor. This occurs because people want to avoid cognitive dissonance, which could arise as a result of behaving in a favorable way toward someone that they either dislike or don’t like enough.
  • Social influence. These are biases that are caused by the influence of various social factors. For example, the outgroup homogeneity bias is a cognitive bias that causes people to view members of outside groups as being more similar to each other than members of groups that they are a part of. This occurs because people tend to allocate more of their attention to members of their own group, since interactions with those people are generally perceived as more important.

Note that some biases can occur due to a combination of reasons. For example, many heuristics-based biases occur due to our limited cognitive capacity, and many biases that have emotional motivation are also affected by social factors.


Hot vs. cold biases

Another criterion which is sometimes used in order to categorize cognitive biases is the distinction between hot biases and cold biases:

  • Hot biases are biases which are motivated by emotional considerations, such as our desire to have a positive self-image, or our need to feel that we made a choice that is valid from a moral perspective. For example, the self-serving bias is a cognitive bias that causes people to ascribe their successes to their own efforts and abilities, while at the same time ascribing their failures to external causes. This bias occurs due to people’s need to enhance their self-esteem, and is strongly influenced by various emotional considerations.
  • Cold biases are biases that occur due to emotionally-neutral processes, such as our intent to make an optimal choice, or our intent to make a decision quickly. For example, the telescoping effect is a cognitive bias that causes people to perceive past events as being more recent than they are, and recent events as being more remote. This bias occurs due to the way our memory works, and isn’t generally affected by any emotional considerations.

As with the other criteria that are used in order to categorize cognitive biases, the hot/cold distinction can sometimes be difficult to apply when it comes to the occurrence of certain biases, that are affected by emotional considerations only to a small degree. Nevertheless, the hot/cold distinction can be valuable in many cases, and can be used in conjunction with other criteria in order to categorize cognitive biases and understand why they occur.


Cognitive debiasing

The problem with cognitive biases and the importance of debiasing

As we saw so far, cognitive biases can be problematic, because they distort our thinking and cause us to make sub-optimal decisions.

For example, the ostrich effect is a cognitive bias that causes people to avoid situations where they might encounter information that they don’t want to deal with. This is an issue, since this bias can cause us to avoid acquiring important information, such as information on how to deal with a medical condition that we have, or information on the performance of one of our investments. Being able to mitigate the ostrich effect is therefore beneficial, since it could prompt you to acquire useful information that you would otherwise avoid.

Accordingly, learning how to debias yourself successfully can be beneficial in many situations, by helping you think more clearly, and by helping you make better decisions.

Furthermore, debiasing techniques can also be beneficial when you apply them to other people, since they can help you communicate more effectively, and encourage others to be more rational.

For example, by knowing how to mitigate the backfire effect, which as we saw above causes people to strengthen their support of their original stance in the face of evidence that they are wrong, you can improve your ability to persuade people when presenting them with evidence that they don’t want to hear.


How to debias

As we saw earlier, cognitive biases occur as a result of three possible issues with our cognitive systems:

  • Failure of System 1 (our intuitive system) to generate correct intuitions.
  • Failure of System 2 (our reasoning system) to monitor and correct System 1.
  • Failure of System 2 to carry out a proper reasoning process.

Based on this, there are three main things that you can do in order to mitigate cognitive biases:

  • Help System 1 generate better intuitions. To do this, you need to train System 1 to instinctively reach optimal solutions. You can accomplish this by practicing the formation of intuitive impressions, while providing this System with feedback which helps it learn how to improve.
  • Help System 2 monitor System 1 better. To do this, you need to help System 2 identify cases where System 1 leads to sub-optimal solutions, so that System 2 can handle them properly. You can accomplish this by implementing relevant metacognitive strategies, which prompt System 2 to monitor System 1 better.
  • Help System 2 form better judgments. To do this, you need to improve your conscious reasoning process, in order to ensure that System 2 reaches optimal solutions. You can accomplish this by implementing relevant metacognitive strategies, which promote a more effective reasoning process.

Note that in this context, metacognitive strategies are strategies that you can apply in order to regulate your cognition.

Different metacognitive strategies will be applicable in different scenarios. These strategies can be fairly simple and universal, such as increasing your awareness of the bias in question, or they can be more specific, such as creating psychological distance in order to mitigate the egocentric bias, which is the tendency to anchor other people’s viewpoint to your own.

With enough practice, the application of metacognitive strategies can become intuitive. However, their application can be effective even at an early stage, where you have to consciously remind yourself to use them. This stands in contrast with training System 1 to form better intuitions, which generally requires a significant amount of practice in order to reach a meaningful improvement in performance.

Overall, this section describes the basic idea behind cognitive debiasing. Since the concept of debiasing warrants a comprehensive discussion of it by itself, the current article doesn’t expand on it further. If you want to learn more about the debiasing process and about how to debias effectively, read this in-depth guide on the topic.


A few notes on cognitive biases and our cognitive systems

Cognitive biases aren’t necessarily bad

So far, we saw that cognitive biases can cause a variety of issues. However, while cognitive biases cause us to think in an irrational way, it is incorrect to say that cognitive biases always affect us in a negative manner. Rather, cognitive biases can sometimes influence our thought process in a positive way, that helps us make optimal decisions.

For example, the pessimism bias is a cognitive bias that causes people to overestimate the likelihood that negative things will happen to them. This bias can have a negative impact in some cases, such as when it causes people to avoid trying to cope with a difficult situation, by leading them to assume that they will inevitably fail, regardless of their efforts.

However, the pessimism bias can also serve as an adaptive coping mechanism in some cases, such as when it is used as a defensive strategy that encourages people to think through risky future situations. In such cases, this cognitive bias prompts people to prepare for the future, by encouraging them to think about all the possible obstacles that they might encounter, as well as of ways to overcome those obstacles.

Furthermore, many biases are seen as beneficial heuristics, which, as we saw earlier, are mental shortcuts that involve the use of efficient rules in order to simplify complex problems and make decisions quickly, at the potential cost of missing the best possible solution to the problem.

Accordingly, from an evolutionary perspective, cognitive biases are sometimes seen as design features rather than design flaws, meaning that they are viewed as adaptive behavior, that can be beneficial in many cases.

Overall, the important thing to remember is that cognitive biases can sometimes aid your thought process, and enable you to make decisions in an optimal way, even if they distort your view of the situation. At the same time, however, it’s still important to be aware of them, so that you can evaluate their effect, and determine whether or not you will benefit from reducing their influence.


The role of perception

Our perception system, which is responsible for our ability to perceive input, is considered to be distinct from our two other cognitive systems (System 1 and System 2).

There are some similarities between our perception system and System 1, since they both consist primarily of automatic subconscious processes that run in parallel to each other. However, our perception system is different from System 1 in some ways, due to the fact that it’s:

  • Relatively neutral, as opposed to System 1, which is influenced by various emotional and social considerations.
  • Evoked by direct stimulus only, as opposed to System 1, which can be evoked by things such as language or thought.
  • Limited to perceptual representations, as opposed to System 1, which can generate abstract representations.
  • Limited to stimuli that we encounter in the present, as opposed to System 1, which can also deal with information that relates to the past or the future.

Essentially, our perceptual system provides us with information that is fed into System 1, in order to form intuitive impressions. Then, these impressions undergo deliberate operations of reasoning by System 2, in order to form conscious judgments.


The history of cognitive biases

Cognitive biases have affected humans and other animals from an early stage of our development, and scientists have long known that people sometimes think in an irrational way.

However, the idea that irrational decisions occur as a result of systematic biases in our cognitive systems was made prominent in the early 1970s by two researchers, Amos Tversky and Daniel Kahneman, in a series of papers on the topic:

The two earlier papers served primarily to introduce the concept of heuristics under the framework described by Tversky and Kahneman, while the 1974 paper became the best-known article on the topic, and introduced cognitive biases as we know them today.

Kahneman later went on to win the 2002 Nobel Prize in Economics for his joint work with Tversky, who died in 1996. (Note: the Nobel Prize is not awarded posthumously).


The difference between cognitive biases and logical fallacies

While cognitive biases and logical fallacies are similar, they represent two distinctly different things:

  • Cognitive biases are systematic errors in cognitive processing (a psychological concept).
  • Logical fallacies are flawed patterns of argumentation (a philosophical concept).

This means that cognitive biases occur at a more basic level of thinking, and can therefore lead to the use of various logical fallacies.

For example, consider the appeal to nature, which is a logical fallacy where something is assumed to either be good because it’s considered ‘natural’, or bad because it’s considered ‘unnatural’. This fallacy could potentially be rooted in some cognitive bias that causes people to instinctively prefer things that they perceive as ‘natural’, and to reject things that we perceive as ‘unnatural’.

However, this doesn’t mean that the use of a logical fallacy is always rooted in some cognitive bias.

For example, consider the strawman fallacy, which is a logical fallacy where someone presents a distorted version of their opponent’s argument, in order to make it easier for them to attack. While someone might use a strawman argument because they misunderstand their opponent’s argument due to some cognitive bias, it’s also entirely possible to use such arguments consciously, while being aware that you are doing so, and without being driven to it by any bias.

Overall, the main distinction between cognitive biases and logical fallacies is that biases are a psychological concept, while fallacies are a philosophical concept. Biases can sometimes prompt the use of certain fallacies, but the two aren’t always related, and the use of fallacies can occur without a cognitive bias being involved.


How to learn more about cognitive biases

If you are interested in the topic of cognitive biases, and would like to learn more about them and about the way people think and make decisions, here are a few recommended books that you should look at:

  • Thinking, Fast and Slow (by Daniel Kahneman)- this is the foremost book to read if you want to understand how our cognitive systems work and why we have cognitive biases.
  • Predictably Irrational (by Dan Ariely)- this book will help you understand the systematic patterns of irrationality that people display when they make decisions.
  • The Art of Thinking Clearly (by Rolf Dobelli)- this book will help you learn about common biases that we encounter in our everyday life.


Summary and conclusions

  • Cognitive biases are systematic patterns of deviation from rationality, that cause us to be irrational in the way that we search for, evaluate, interpret, judge, use, and remember information.
  • We experience cognitive biases when we fail to correct faulty intuitive impressions, or when we fail to conduct a valid reasoning process. Both these issues occur as a result of the way that our cognitive systems work.
  • Cognitive biases can be categorized based on the area of cognition in which they affect us (e.g. decision-making or memory), and based on their cause (e.g. social influence or limited cognitive-capacity). Biases can also be categorized based on a hot/cold distinction, with hot biases being motivated by emotional considerations and cold biases being driven by emotionally-neutral processes.
  • Cognitive biases can affect us negatively in many areas of life, when they cause us to find sub-optimal solutions to our problems. However, biases can sometimes be beneficial, such as when they help us find quick solutions to our problems.
  • It’s possible to debias yourself and others successfully through the use of metacognitive strategies, which can help you conduct a valid reasoning process. Furthermore, you can reduce the number of biases that you experience by training yourself to form better intuitive impressions.


Overall, the topic of cognitive biases is fascinating, and there is a lot that you can learn about it. Accordingly, if you want to read more about cognitive biases, three recommended books are Thinking, Fast and Slow“, “Predictably Irrational“, and “The Art of Thinking Clearly“.