The Basic Idea

We all know someone who always sees the positive side of a situation. They’re a glass-half-full individual, always believing that good things will happen to them. They view their life from the perspective of a main character in a movie, trusting that somehow, things will work out.

While not everyone feels quite this positive all of the time, in general, humans tend to be overly optimistic. We often overestimate the likelihood of positive things happening to us and underestimate the likelihood of negative things happening to us. This tendency leads us to engage in behaviors that may not be rational, such as not saving for an emergency fund or buying a lottery ticket, despite the odds of winning being very low. Equally, we might undertake risky behaviors like riding a bike without a helmet or driving under the influence, because we tell ourselves “bad things won’t happen to me.”

But it also goes without saying that optimism comes with plenty of advantages. Research shows that optimism is linked to improved physical and mental health, including better sleep, reduced anxiety, and lower rates of depression.1 Positive psychology, a branch of psychology that focuses on what allows people to thrive and lead happy, healthy lives, tends to view optimism as a means of increasing one’s well-being.2

How do we reconcile these contradictory views on optimism? There might be a happy medium. Instead of positioning people within a rigid dichotomy, with optimism on one side and pessimism on the other, we might think of optimism on a spectrum. Read on to learn more about the pros and cons of a glass-half-full attitude, and how optimism can help (or hinder) your everyday life.

The good news is that awareness [of the optimism bias] rarely shatters the illusion. The glass remains half full. It is possible to strike a balance, to believe we will stay healthy but get medical insurance anyway; to be certain the sun will shine but grab an umbrella on our way out the door – just in case.

– Neuroscientist Tali Sharot, in her bookThe Optimism Bias: A Tour of the Irrationally Positive Brain3

Theory, meet practice

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Key Terms

Expectancy-value theory: a theory first developed by John William Atkinson. This theory suggests that motivation for behavior is determined by two factors: expectancy of success (i.e. the likelihood that doing something will lead to the desired outcome), and how much the individual values said desired outcome.4

Optimism bias: our tendency to overestimate the likelihood of positive events and underestimate the likelihood of negative events occurring to us.

Hindsight bias: our tendency to look back at unpredictable events and see them as easily predictable, as though it is obvious that the event was going to happen all along.

Positive psychology: a branch of psychology that explores what characteristics and human behaviors allow individuals to lead meaningful and happy lives. Positive psychology concerns itself with things that can increase well-being.5

Learned optimism: a concept that describes how optimism can be practiced and learned over time, a process that can help maximize our wellbeing.6


The term “optimism” has been around since 1710, when philosopher Gottfried Leibniz used it referring to the “best of all possible worlds.” 7

In the 1950s and 1960s, John William Atkinson developed the expectancy-value theory, which demonstrated that one’s expectations of success affects one’s motivation to complete a task. If someone feels optimistic about their likelihood to succeed, they actually become more motivated to work hard in that task. Atkinson conducted various studies showing that children who were optimistic about their success led to greater engagement and continued interest in school material, and academic achievement.8

It wasn’t until 1980 that psychologists began to look at the other side of optimism: the negative impacts it has on our decision-making. Psychologist Neil Weinstein studied what he termed “unrealistic optimism” by asking college students to estimate their chances of experiencing a certain event, as well as those of their classmates. He found that students thought their chances of experiencing a negative event was lower than that of their classmates, whereas they believed their chances of experiencing a positive event was higher than that of their classmates. The phenomenon has become known as the optimism bias, which describes people’s tendency to underestimate the likelihood that they will experience negative events and overestimate the likelihood that good things will happen to them.9

One of the most notable figures who has spoken extensively on the positive impact of optimism is the father of behavioral science himself, Daniel Kahneman. He has said that being optimistic is wonderful because “it keeps you healthy and it keeps you resilient.”10 Kahneman also believes that optimistic people, because they look at the world in a positive way, are more likely to be innovative and come up with creative solutions to society’s problems—which is why we tend to favor optimistic leaders.10

Interestingly, Kahneman has noted that many great innovations have actually emerged from optimism bias: “The people who make great things, if you look back, they were overconfident and optimistic—overconfident optimists. They take big risks because they underestimate how big the risks are.”11 In other words, irrational optimism can still pay off if luck is on your side.

When it comes to explaining why people tend to be overly optimistic, Kahneman attributes it to the hindsight bias.The hindsight bias describes our tendency to see unpredictable events as predictable after they occur. After something has occurred, people are led to believe it was obvious it was going to happen all along, so there is no need to change anything about their optimistic behavior going forward. But bad things can happen randomly, no matter how we behave, which means at some point or another, they will probably happen to us.11


A meta-analysis of 83 different studies showed that optimism is linked to better health outcomes, including cardiovascular disease, cancer, pain, and mortality. Optimistic individuals also have generally better mental health compared to those who lean towards pessimism, since optimism helps to reduce depression, anxiety, and stress. Research also shows that being optimistic can make individuals feel more motivated, which increases the likelihood of a positive outcome in many situations.12

If you’re more of a pessimist, reading all this might have you feeling somewhat worried. But don’t despair: according to the founder of the positive psychology movement, Martin Seligman, not only can we learn to become more optimistic, it is important for us to do so to maximize our life satisfaction. Funnily enough, Seligman began his career studying pessimism, but a friend pointed out that instead of focusing on problems, his work was examining how to fix them and actually had more to do with optimism.12

Optimistic and pessimistic people also tend to have different explanatory styles. An optimistic explanatory style is when individuals explain the causes of positive events as being related to internal factors, such as actions or characteristics. Since they relate them to more stable factors, they predict that positive things will continue happening. If something bad happens to someone with an optimistic explanatory style, they will blame it on external events that are out of their control, which causes them to perceive it as a fluke. The pessimist explanatory style is the opposite - negative events are attributed to internal characteristics, and positive events are attributed to fluke external factors.2


We have already discussed the optimism bias that contradicts the aforementioned positive impacts of optimism. According to the optimism bias, optimism actually hinders our lives because we make risky decisions that can have disastrous outcomes. It clouds our judgements and can cause us to put ourselves in a dangerous situation or make a risky investment.

Yet, not all psychologists believe that optimism can impact our health. American psychologist James C. Coyne has said that he “certainly do[esn’t] buy into the idea that positive attitudes can somehow mysteriously directly influence physical health outcomes.” 13 Coyne made this statement after conducting a study where he found that emotional well-being (or optimism) did not predict survival in cancer patients.

However, even if optimism doesn’t have a direct influence on our health, it might still have an indirect one. Feeling optimistic might push us to take actions that lead to better outcomes. Optimism also keeps individuals feeling happy and positive, which has shown to have a positive influence over our health.

It seems that whether optimism directly or indirectly guides our wellbeing, or whether it has more positive or more negative impacts on our lives, it can’t be ignored as an influential factor.

Optimism and the ABC model

The concept of learned optimism speaks to the fact that our attitudes about the world are not static. We are not inherently born an optimist or pessimist, but can change our attitudes over time. This phenomenon is the opposite of learned helplessness, whereby individuals believe they are incapable of changing their circumstances and are doomed to continue experiencing stressful events.14

If optimism can be taught, we should look at what kind of techniques exist to help people inch closer towards the optimistic side of the spectrum. One useful framework to guide this process is Albert Ellis’s ABC model. Ellis was the founder of rational emotive behavior therapy (REBT), a branch of cognitive behavioral therapy (CBT) which helps individuals to identify and alter the irrational beliefs that are at the core of their mental distress.15

The components of the ABC model are as follows:

A: Activating Events

B: Beliefs

C: Consequences

Essentially, Ellis wanted his patients to realize that external activating events (A) do not directly lead to negative consequences (C). Instead, it is the way that we interpret these events (our beliefs, B) that causes negative outcomes.

This model emphasizes the fact that we are the ones in control of the consequences, because they are based on our beliefs and not on external factors. Although someone can’t always change their environment and what happens to them, they can learn to be more optimistic about the events, which in turn, will allow them to avoid negative consequences and feel happier.15 Indeed, studies have shown that optimistic people have greater confidence in their ability to control their lives. This is known as an internal locus of control.14

Cognitive behavior therapies like REBT have been found to be effective in reducing negative beliefs. In fact, one study found that individuals who participated in learning sessions about the ABC model had reduced symptoms of depression and anxiety and increased feelings of hope and increased self-esteem.16 Based on this, simply reading about the ABC model in this article might have helped you become more optimistic and be happier!

Optimism and COVID-19

Through the COVID-19 pandemic, it has been difficult for many of us to feel optimistic about our lives or the state of the world, with a relentless stream of bad news continuing for months on end. But could optimism actually help us fend off the disease?

Canadian psychologists Mega Leung, Gökmen Arslan, and Paul Wong published a study in September 2021 which examined whether tragic optimism could compensate for factors that diminish life satisfaction. Tragic optimism is a distinct type of optimism that can be characterized as more realistic, where one acknowledges the existence of loss and suffering while still finding pockets of hope. The concept was first proposed by psychologist and holocaust survivor Viktor Frankl, who suggested that tragic optimism can help individuals survive extreme hardships, such as his own.17

Leung and her colleagues surveyed people’s experience of the COVID-19 pandemic all over the world, where individuals were asked about their life attitudes and how much they had suffered because of the global virus. Life attitude questions asked people to rate their agreement with statements like “My life is worth living no matter how many problems I have” on a scale. They found that individuals who displayed tragic optimism reported less suffering. Their outlook helped them maintain life satisfaction despite what they had lost.18

However, optimism during COVID-19 can also have negative effects. A study conducted by anthropologist Jeffrey Gassen found that unrealistic optimism was causing individuals at higher risk for severe COVID-19 to engage in risky behaviors. Because of their optimism, their actions were misaligned with their vulnerability to the disease.19

Related TDL Content

The Vaccine Optimism Effect: Why Vaccine News Might Reduce Social Distancing

When vaccine rollouts first began, we finally began to see light at the end of the dark COVID-19 tunnel. Finally, we were able to hope that the end was near and be optimistic about our ability to survive the global pandemic. While the media had so long focused on the negative, now, there was a positive story being spun. However, as contributor Natalie Tham discusses in this article, the optimism we felt because of vaccine rollouts actually has some negative effects. The vaccine gave some of us a false sense of security, and led us to disregard the ongoing need for safety measures.

Optimism Is Good For Many Things, But Not Pension Savings

When it comes to our finances, optimism can lead us to believe that we’ll make more money in the future, so there’s no harm in spending it now. We think that if we’re missing some money for our retirement needs, we can just retire a little later than planned, not factoring in that something could happen to us which would prevent us from continuing to work. In this article, contributor Žiga Vižintin looks at how the optimism bias negatively affects our pension savings.


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  12. Cherry, K. (2021, June 28). Using Learned Optimism in Your Life. Verywell Mind. https://www.verywellmind.com/learned-optimism-4174101
  13. Moore, C. (2020, August 6). Learned optimism: Is Martin Seligman’s glass half full? PositivePsychology.com. https://positivepsychology.com/learned-optimism/
  14. Mcleod, S. (2019). Cognitive Behavioral Therapy. Simply Psychology. https://www.simplypsychology.org/cognitive-therapy.html
  15. Selva, J. (2018, February 17). Albert Ellis’ ABC Model in the Cognitive Behavioral Therapy Spotlight. PositivePsychology.com. https://positivepsychology.com/albert-ellis-abc-model-rebt-cbt/
  16. Volpe, A. (2021, March 8). 'Tragic optimism': The antidote to toxic positivity. BBC. https://www.bbc.com/worklife/article/20210302-tragic-optimism-the-antidote-to-toxic-positivity
  17. Leung, M. M., Arslan, G., & Wong, P. T. (2021). Tragic optimism as a buffer against COVID-19 suffering and the psychometric properties of a brief version of the life attitudes scale. Frontiers in Psychology, 12. https://doi.org/10.3389/fpsyg.2021.646843
  18. Gassen, J., Nowak, T. J., Henderson, A. D., Weaver, S. P., Baker, E. J., & Muehlenbein, M. P. (2021). Unrealistic optimism and risk for COVID-19 disease. Frontiers in Psychology, 12. https://doi.org/10.3389/fpsyg.2021.647461
  19. Positive psychology Quotes. (n.d.). Goodreads. Retrieved October 21, 2021, from https://www.goodreads.com/quotes/tag/positive-psychology

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