The evolution of optimism

There is a lot of information out there about the benefits of optimism in numerous areas of life. The research shows that optimists aren’t necessarily blind to the world, seeing it with rose-tinted glasses, which is a common criticism of books and programs aimed at developing optimism in people. In fact, optimism seems to be in many cases a highly desirable decision making or belief strategy. And being optimistic implies a positive anticipation of a desired outcome; sometimes when all the evidence points to a different one occurring.

Rather than writing the “10 steps to optimism”, I want to look into this a little more deeply. Why have we evolved the ability to think this way? Surely the best way to guide behaviour would be to hold beliefs that are as accurate as possible, and making decisions based on them. I would have assumed that these would be the most accurate decisions you could make. So you might argue that natural selection would tend towards accurate thinking, but this doesn’t match up with the evidence base on optimism or other cognitive biases (or simply the experience of being human).

To explain the ultimate origin of optimism, it is necessary to figure out whether having a system in the brain that allows for overly favourable perception or cognition can be beneficial to survival or reproduction, and also to see how the system would relates to other ideas in evolutionary theory.

To give a specific example, consider the tendency of men to overestimate the sexual interest of women (1). This is of course an adaptive strategy, because male reproduction is limited only by the number of partners they can meet, and since it costs little or nothing to ‘try it on’, being optimistic and assuming the best means fewer missed opportunities. Natural selection would therefore favour men who are optimistic about women’s interest in them, as opposed to those with accurate perceptions.

This balance of costs and benefits is how optimism is said to have evolved. In a situation where a caveman or cavewoman has to make a decision, but they are uncertain about the outcome, sometimes they are going to get it wrong. But, is it more costly to make false positive errors, or false negative errors? This problem is called error management theory (1), and it ties in nicely with the idea of positive illusions, which we’ve discussed before in the context of relationships.

Taylor and Brown (2) propose that positive illusions help motivate people to pursue goals with a low objective level of success, such as the terminally ill individual whose positive illusion about the disease leads her to positive health behaviours.

In such a situation (and in others), optimism and pessimism can lead to different negative outcomes – optimism might lead to wasting time and energy in pursuits that are not beneficial, and pessimism might lead to passivity and missing out on potential opportunities.

Reasoning forward we can see a route through which optimism can evolve in a world where the outcomes of decisions are often uncertain – if the cost of trying and failing is low (compared to the benefit of succeeding), then optimism is the best strategy – better, even, than a decision that is made on accurate information (3).

Coming back to increasing chances of survival and reproduction, we find that positive illusions tend to be aimed toward the self, and particularly about characteristics that other people find desirable – when asked about others, the illusions disappear (4) – with the exception of our positive illusions towards our romantic partners; but we’ve seen that these are ultimately self-serving as they help sustain the relationship.

Likewise, pessimism is thought to have evolved by the same pressure of natural selection, but this time acting on a different area of the brain. This allows for variation in the things we can be optimistic and pessimistic about, depending on the particular situation (see reference 3 for more info on this).

Recommended Reading


(1)Haselton, M. G. & Buss, D. M. (2000). Error management theory: A new perspective on biases in cross-sex mind reading. Journal of Personality and Social Psychology, 78, 81-91.

(2) Taylor, S. E., & Brown, J. D. (1988). Illusion and well-being: A social psychological perspective on mental health. Psychological Bulletin, 103, 193-201.

(3) Haselton, M., & Nettle, D. (2005). The paranoid optimist: An integrative evolutionary model of cognitive biases. Personality and Social Psychology Review, 10(1), 47-66

(4) Campbell, J. D. (1986). Similarity and uniqueness: The effects of attribute type, relevance and individual differences in self-esteem and depression. Journal of Personality and Social Psychology, 50, 281-294.


  • Diggy says:

    Just found your blog for the first time, I like it 🙂

    I think that optimism is very imporatant in life. Optimistic people always seem to have more friends, more success and more opportunities. Maybe it has to do with tha law of attraction. I.e. because you are optimistic you will attract others who are optimistic and you will be more open for good opportunities.

    Keep up the cool articles!
    .-= Diggy´s last blog ..The 4 Stages of Mastery =-.

    • Warren Davies says:

      Hi Diggy, thanks for the comment and compliment!

      Personally, I think the effectiveness of optimism has to do with its general effectiveness as a decision making strategy. It has about as much to do with the law of attraction as it does the Jolly Green Giant!


  • The blog of yours is really inspiring! I love the feature about being an optimistic because I can apply it as I am in the business.And it was once quote that “Positive things happen to positive people.”
    .-= Internet Marketing Professor´s last blog ..Social Media Tips: LinkedIn for Business =-.

  • joe says:

    wow, this is a very deep article and very well written I mite add!
    .-= joe´s last blog ..What triggers male hair loss? =-.

  • harry says:

    I think that the optimism is the best life style. it is much easier to coop with bad things that happens in someone’s life.

    And i think that optimistic people are way more creative and satisfied in there life.
    .-= harry´s last blog ..£10,000 Daily Jackpots on Mecca Bingo =-.

  • aussie blog says:

    Very deep and comples article. Always look at the bright side I always say. 🙂
    .-= aussie blog´s last blog ..Flooded office =-.

  • Jeff says:

    I agree that optimism probably have survival reasons for being so important. Clearly an optimist person who does not give up in any situation in the face of a challenge is better suited than someone who just gives up!
    .-= Jeff´s last blog ..Usual vitamin deficiencies for certain lifestyles =-.

  • bombshock says:

    I beleive any animal “deap seated” human predisposition can be overpowered by intellect and reason. Starting with not hiding the truth from oneself.. “Lying to oneself”. Essentially, taking control of your animal side leads to a much more positive life all round. Optimism may have treated our ancestors well, but surely it is time we identify and reason with these tendancies which no longer serve us in any meaningful way?

  • Personally, I believe strongly that our thoughts affect our general psychological state. Persistent thoughts create a cognitive map, which in turn affects our emotions and thus our attitudes. Our attitude totally affects our behaviour.

    What we do essentially creates our results and thus our destiny in life.

    .-= Daniel@the law of attraction simplified´s last blog ..Debunking the Law of Attraction =-.

  • Ya I think optimism is a core thing. It defines everything… Lets say you have a failure, if your optimistic you might get back up and move on and try again quicker. If your not.. you might just dwell and waste hours/days/years on a single failure while putting yourself down!

  • If you are purporting these evolutionary psychology ideas to be science, you really should at the very least acknowledge that one needs to be much more rigorous about it than this. For example, you say that the tendency of men to overestimate the sexual interest of women “is of course an adaptive strategy”. How do you know? You only think so because it makes sense. However, in evolution things aren’t always as straightforward as the adaptationist would have it.

    Here’s what Jerry Coyne says about adaptations:

    “But an evolutionary adaptation is more than something that is merely useful. Biologists consider a trait adaptive only if that behavior, and the genes producing it, enhance an individual’s fitness—the average lifetime output of offspring. It is this genetic advantage, and the evolutionary changes in behavior it promotes, that is the essence of adaptation by natural selection. To demonstrate that depression is an evolved adaptation, then, we must show that it enhances reproduction.”

    Merely talking about optimism being adaptive, saying it seems plausible, is not enough to accept that hypothesis.

  • Warren Davies says:

    Thanks for the thoughtful comment Bjørn!

    “For example, you say that the tendency of men to overestimate the sexual interest of women “is of course an adaptive strategy”. How do you know? You only think so because it makes sense. However, in evolution things aren’t always as straightforward as the adaptationist would have it.”

    Quite right, I guess I was getting carried away there. Consider my hand slapped!

    “Merely talking about optimism being adaptive, saying it seems plausible, is not enough to accept that hypothesis.”

    To clarify, I’m not saying this hypothesis should be accepted, just throwing some ideas around. But you’re right I should have made that more clear.

  • Kudos.
    .-= Bjørn Østman´s last blog ..Biologists counter creationist movie =-.

  • Stork Club says:

    For me being optimistic is what keeps us going even in the darkest of days.Positive illusions,even if it is an illusion can create a big impact, maybe of hope of looking forward to something better.

  • Henway says:

    @bombshock I think you’re right to an extent. Surely we should not exercise ALL our animal instincts or else society will become a total disaster.

    But we should acknowledge some of them, and find ways to exercise them positively and constructively. Evolution has made a certain way, and it’s not good to repress those feelings. Our lives would be easier if we learn what evolution had made us into, and pursue positive actions that are both wholesome and satisfy those evolutionary instincts.
    .-= Henway´s last blog ..GoDaddy for Hosting =-.

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