Understanding the Optimism Bias

AKA the Illusion of Invulnerability

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While we often like to think of ourselves as highly rational and logical, researchers have found that the human brain is sometimes too optimistic for its own good. If you were asked to estimate how likely you are to experience divorce, illness, job loss, or an accident, you are likely to underestimate the probability that such events will ever impact your life.

What Is the Optimism Bias?

Your brain has a built-in optimism bias. The phenomenon is also often referred to as "the illusion of invulnerability," "unrealistic optimism," and a "personal fable."

This bias leads us to believe that we are less likely to suffer from misfortune and more likely to attain success than reality would suggest. We believe that we will live longer than the average, that our children will be smarter than the average, and that we will be more successful in life than the average. But by definition, we can't all be above average.

The ​optimism bias is essentially a mistaken belief that our chances of experiencing negative events are lower and our chances of experiencing positive events are higher than those of our peers.

This phenomenon was initially described by Weinstein in 1980, who found that the majority of college students believed that their chances of developing a drinking problem or getting divorced were lower than their peers. At the same time, the majority of these students also believed that their chances of positive outcomes like owning their own home and living into old age were much higher.

Impact of the Optimism Bias

The optimism bias doesn’t mean that we have an overly sunny outlook on our own lives. It can also lead to poor decision-making, which can sometimes have disastrous results. People might skip their yearly physical, not wear their seatbelt, not add money to their emergency fund, or fail to put on sunscreen because they mistakenly believe that bad things won't happen to them.

Cognitive neuroscientist Tali Sharot, author of The Optimism Bias: A Tour of the Irrationally Positive Brain, notes that this bias is widespread and can be seen in cultures all over the world. Sharot also suggests that while this optimism bias can at times lead to negative outcomes like foolishly engaging in risky behaviors or making poor choices about your health, it can also have its benefits.

Benefits of the Optimism Bias

If we expect good things to happen, we are more likely to be happy. This optimism, Sharot also explained in a 2012 TED Talk, can act as a self-fulfilling prophecy. By believing that we will be successful, people are in fact more likely to be successful.

This optimism enhances well-being by creating a sense of anticipation about the future.

Optimism also motivates us to pursue our goals. After all, if we didn't believe that we could achieve success, why would we even bother trying? Optimists are also more likely to take measures to protect their health such as exercising, taking vitamins, and following a nutritious diet.

Causes of the Optimism Bias

So why are we so geared toward optimism? Experts believe that our brains may be wired by evolution to see the glass half-full.

Researchers have suggested various causes that lead to the optimism bias, including cognitive and motivational factors. When we are evaluating our risks, we compare our own situation to that of other people, but we are also egocentric. We focus on ourselves instead of realistically looking at how we compare to others.

But we are also highly motivated to be so optimistic. By believing that we are unlikely to fail and more likely to succeed, we have better self-esteem, lower stress levels, and better overall well-being.

The Optimism Bias Conundrum

Optimism bias increases the belief that good things will happen in your life no matter what, but it may also lead to poor decision-making because you're not worried about risks.

Contributing Factors

The following are some of the factors that make the optimism bias more likely to occur:

  • Infrequent events are more likely to be influenced by the optimism bias. People tend to think that they are less likely to be affected by things like hurricanes and floods simply because these are generally not everyday events.
  • People experience the optimism bias more when they think the events are under the direct control and influence of the individual. As Sharot described in her TED Talk, it's not that people believe things will magically work out, they think that they have the skills and know-how to make it so.
  • The optimism bias is more likely to occur if the negative event is perceived as unlikely. If for example, a person believes that getting skin cancer is very rare, he or she is more likely to be unrealistically optimistic about the risks.

Below are some of the factors that decrease the optimism bias:

  • Actually experiencing certain events can reduce the optimism bias.
  • People are less likely to experience the optimism bias when they are comparing themselves to very close loved ones such as friends and family members.
  • Research published in 2011 has also shown that people who are depressed or anxious are less likely to experience the optimism bias.

Optimism Bias Research

While researchers have attempted to help people reduce the optimism bias, particularly to promote healthy behaviors and reduce risky behaviors, they have found that reducing or eliminating the bias is actually incredibly difficult.

In studies that involved attempts to reduce the optimism bias through actions such as educating participants about risk factors, encouraging volunteers to consider high-risk examples, and educating subjects and why they were at risk, researchers have found that these attempts led to little change and in some instances actually increased the optimism bias.

For example, telling someone the risks of dying from a particular habit such as smoking can actually make them more likely to believe that they will not be negatively affected by the behavior.

9 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Kendra Cherry, MSEd
Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."