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This blog will change how you judge

By Mastery5 min read

How do you make judgements?

Would you be surprised if I told you that many of your judgements had little to do with the facts at all? Consider even the most rational of all choices: what company to invest in. How would you choose to invest your hard-earned money: a review of their trading record, a careful analysis of their annual report or an evaluation of the market trends in that industry? How about how nice their name was?

It turns out, people’s choices of company to invest in are significantly affected by the name (or more specifically by the three-letter ‘ticker’ symbol that stock exchanges use). In a study of real-world investments, a basket of shares with easy-to-pronounce names such as KAR outperformed those with less easy names such as RDO by 12% on their first day of trading and 33% over the first year. That’s astonishing in the most hard-bitten, objective of industries.


Whenever you look, remember or think, your brain has to work. Some tasks are easier than others for the brain to process. Easy tasks feel like they flow, whereas harder ones get a bit stuck. Psychologists refer to this mental experience of processing ease as cognitive fluency. The brain likes easy. The brain is also a manic interpretation machine. It interprets the positive feeling of fluency as meaning something positive. So when you come to make a judgement about how much you like something; whether you believe it; or how confident you are, this feeling of fluency influences you. And you will be entirely unaware of this influence.

Which picture do you like more?

Most people prefer the picture on the left. It is a more familiar image – looking like a zebra – than the more geometric one. Familiar images are more fluent than unfamiliar ones. Think of a cave man seeing an elephant for the first time. The brain has to go into over-drive to observe and judge if the elephant is going to eat him or not. Once the man is familiar with elephants, he (and his brain) can easily judge he’s safe. So you can understand why he would come to prefer familiar things to the unfamiliar. The ease of processing becomes a signal for the brain that suggests familiarity; which in turn says ‘Relax. You are not lunch’.

This is called the mere exposure effect. Present unfamiliar images to people. Show some of those images for a little longer than others (400ms compared to 100ms). Afterwards people will reliably prefer the images they saw for longer. Interestingly if you ask the person why they like them more, they will make up a reason – and it won’t be that they saw them for 400 rather than 100ms! The fact is, people are entirely unconscious of the impact of cognitive fluency.

It’s not simply familiarity that influences judgements. Let’s imagine you saw the statement ‘Osorno is in Chile’ and you were asked to judge the truth of this statement, would the clarity of the text affect your judgement? When these statements are shown in clear text (e.g. black text on white) people are more likely to believe the statement than when the contrast is not strong (e.g. blue on black). Or, moving beyond the visual, people judge the aphorism ‘Life is mostly strife’ as being truer than ‘Life is mostly struggle’ because rhymes are fluent. Finally, the author of an essay is judged by experienced professors as being less intelligent if the font is difficult to read or the sentences longer!

Cognitive fluency doesn’t simply affect your judgements about the world, but also about yourself. In a classic study, people were asked to judge how assertive they were. Just before they were asked this question, they were given a task: to recall either 6 or 12 examples of times when they had been assertive. Those who had been asked to remember 6 examples (the easier task) rated themselves as more assertive than those who had to remember 12. This was irrespective of how assertive they actually were! Those asked for 6 examples processed the task more easily and used that experience of cognitive fluency to make their judgement. In this example, the experience of fluency plays a greater role in the judgement than the facts themselves.

This same effect has also been found with happiness. If I asked you to identify 12 examples of happy times in your life (a hard task), you would subsequently rate your life as less happy than if I had asked you to only recall 6 times! The brain unconsciously reasons ‘I’m struggling to think of 12; I can’t be happy.’

Cognitive fluency is pervasive, and unconscious. Everything we do is more or less fluent. This knowledge can be hugely helpful if you want to influence people’s judgements, whether you want people to believe something or like (or buy) something: Make it simple. Make it easy. Make it clear.

If, on the other hand, you want to protect yourself against unconscious influence, the trick is to be aware. Studies show that once people are conscious of a possible bias caused by fluency, they begin to base their judgements on the facts rather than the processing ease. So next time you’re thinking about investing, remind yourself to forget how nice the names are!

Now ask yourself, how are you seduced by the easy?



Alter, A.
L., & Oppenheimer, D. M. (2006). Predicting short-term stock fluctuations by using processing fluency. Proceedings of the National Academy of
Sciences, 103, 9369-9372

Adam L. Alter and Daniel M. Oppenheimer (2009) Uniting the Tribes of Fluency to Form a Metacognitive Nation. Personality and Social Psychology Review; 13; 219 – 235

McGlone, M. S., & Tofighbakhsh, J. (2000). Birds of a feather flock conjointly (?): Rhyme as reason in aphorisms. Psychological Science , 11, 424-428