We’ve all been there: smugly thinking you’re right, only to feel like a fool when it turns out you missed something pretty important. Maybe you honk your horn when the car in front of you comes to a sudden stop – and then you see the pedestrian crossing in front of them. Or you stubbornly declare it's 'escape goat' rather than 'scapegoat'.
Well, it turns out this is a hidden bias in your brain that makes you assume you have all the information you need to make those choices, without considering the key details you don’t have.
In a new paper, psychologists have called this the ‘illusion of information adequacy’, and it’s a paradox that plagues most of us. We know, in theory, we don’t know everything – and yet we behave as if we have all the right information to back up our opinions, decisions, and judgements about other people.
This paradox, the researchers argue, could be causing many of the misunderstandings and conflict in our lives.
“Taking shortcuts is how we manage our complicated world,” psychologist Dr Sandra Wheatley, chartered member of the British Psychological Society who was not involved in the study, told BBC Science Focus.
“When you need to make a snap decision, you base it on your experiences and you usually are correct. But every now and again, you get pulled up short. And, unfortunately, at the moment, there’s an awful lot of information that is being shared that is not accurate and needs to be questioned.”
Published in the journal PLOS ONE, the study involved 1,261 participants. The scientists presented them with a decision to make: whether to merge two schools or keep them separate.
While some of the participants received all of the pros and cons of merging, some only saw the pros and some only saw the cons – but none of the participants knew that they were lacking any information.
It may not come as a huge surprise that the people with the pro-merge information recommended the schools merge, and that the pro-separation group recommended the opposite.
But what’s more surprising is that the participants assumed that the information they had was just as good as everyone else’s – and that they were just as well-equipped to make the decision as anyone else. In fact, those with only half of the information felt more confident in their decision compared to those who had access to both sides of the argument.
These participants also assumed that most other people would make the same decision as they had. And, even when given the full information later, they tended to stick to their original decision.
The phenomenon, the researchers say, does more harm than a little embarrassment when you make a poorly informed decision. In fact, they say that it makes us assume our own subjective truth is the objective truth and stops us from understanding others’ perspectives.
According to Wheatley, the study’s findings “mean we can understand why other people make the decisions they make, and then perhaps forgive them for that.”
She added: “When there is a serious decision, say if you’re making judgements about somebody’s character, it’s important to double check your sources.
“Really, it’s about continuously being open to information that questions and makes you wonder or doubt yourself or doubt others.”
About our expert
Dr Sandra Wheatley is a chartered psychologist and Associate Fellow of the British Psychological Society. She speaks publicly about psychology and parenthood, social relationships, and digital media.
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