An individual has been described by a neighbor as follows: “Steve is very shy and withdrawn, invariably helpful but with little interest in people or in the world of reality. A meek and tidy soul, he has a need for order and structure […], and a passion for detail.” Is Steve more likely to be a librarian or a farmer? (Kahnemann, Daniel, 2011, “Thinking, fast and slow” Introduction Chapter)

What is your answer to this question?

Many people would answer “Librarian!” without considering the other option – just as I did before I heard about Bayesian Rationality and the Representativeness Bias. And as you probably would have answered, had I asked you. To put it in Daniel Kahneman’s words: Our mind might lead us automatically to a wrong answer. But many people are still ignoring the fact that our minds can fool us with ingrained biases. Many call it a trick – or manipulation. As many of us will agree, it is easier to spot the mistakes of others than one’s own and the denial of our own biases is called the ‘bias blind spot’.

As Psychology Today states, “Research also shows that we have a “bias blind spot.” Research by Emily Pronin, a psychologist at Princeton University, and colleagues, has found that people rate themselves as less susceptible to a variety of biases than others. These include things like the hindsight bias (the tendency to think we knew it all along more so after we know the outcome of something. See any poker player losing a hand and then saying they knew what you had as evidence of this), the planning fallacy (tendency to underestimate how long things will take) and the self-serving bias (tendency for all people to think they are better than average).”

The dangerous thing with the bias blind spot is that this bias goes hand in hand with the confirmation bias, the tendency to agree with research supporting and to deny research challenging our own view of the world. Furthermore, we tend to gratefully take credit for success but deny responsibility for failure (see self-enhancing and self-protective bias).

The bias blind spot has a great impact on judgements and decision-making. A judge could think a gift of a friend-attorney would never affect his ability to judge the next case properly. However, when asked about his peers, the same judge would argue that a gift would unconsciously manipulate others into partiality. Another possible impact is denial of biases altogether. Research has shown that the bias blind spot occurs unrelated to intelligence and self-esteem. The bad news is that people with a high bias blind spot are concurrently less likely to learn the ability to manage their biases through de-biasing techniques.

Confronting someone with his behavior impacted by bias might not lead to improvements and rather damage your rapport with your friend or client. Consider carefully leading him to self-reflection rather than lecturing on the latest scientific evidence.

To defend yourself against your own bias blind spot think twice about the impacts of biases on your decision-making and judgement. Always keep your eyes open. Go through de-biasing training and use your full mental capacity when it counts.

Thus, the decisive question is: Are you still denying your biases – or have you become an avid follower of our de-biasing techniques?

PHILIP HATTEMER