Beware of the Illusory Truth Effect!

May 10, 2021 Kira Domratchev General Interest Tags: , , , 2 Comments

The illusory truth effect, also known as the illusion of truth, describes how, when we hear the same false information over and over again, we often come to believe it to be true.

I think this concept is an important one to consider for litigators, as we are often embroiled in files that last many years on end. In fact, so much information is often exchanged over a given period of time, that you start to question what really happened. I certainly find myself doing just that on many long playing files.

The trouble with this phenomenon is that most well-informed individuals are prone to this bias and particularly in the age of social media where we often see the same information repeatedly, it is a real issue.

You would think that before deciding whether a claim is true or false, one would compare the claim to available evidence?

Unfortunately, we have to make countless decisions on a daily basis and we simply do not have the time to engage in a lengthy process of comparing and contrasting with respect to every call that needs to be made. We rely on many shortcuts, called heuristics, that can lead to errors in our judgment.

Why Does It Happen?

According to renowned behavioural economist, Daniel Kahneman, there are two thinking systems in our brain: a) System 1 – is fast and automatic, working without our awareness; and b) System 2 – that handles deeper, more effortful processing, and is under our conscious control. Given the amount of decisions we need to make in a day, we tend to rely on System 1, a lot more often than System 2.

Why Is It Important?

In the era of the Internet, we are surrounded by false rumours, conspiracy theories and very often, outright lies. Furthermore, the illusory truth effect doesn’t just affect us by accident, as propagandists understand that repetition is key to forcing people to accept their message.

Importantly, How Do We Avoid It?

This type of bias is quite tricky to avoid, given how pervasive our use of System 1 thinking is. For that reason, critical thinking is the best tool at tackling this issue. In other words, fact-checking your claim the first time you hear it is important in order to reduce the power of the illusory truth effect.

To learn more about this, check out an article by The Decision Lab entitled “Why do we believe misinformation more easily when it’s repeated many times?” here.

Thanks for reading.

Kira Domratchev

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  1. David Blair 1 month Reply

    I loved the reading and look forward to more.

    • Hull & Hull LLP 1 month Reply

      Thank you for your comment, we’re glad you enjoy our content!

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