‘People are dishonest. Much more than they think’

Sophie van der Zee, Assistant Professor at Erasmus School of Economics

Lying is a daily habit for everyone and yet we never get used to lies. Sophie van der Zee, Assistant Professor in the department of Applied Economics at Erasmus School of Economics, discusses her research on how to make people more honest in an interview with de Belgian newspaper De Standaard. Van der Zee is often called a “lie expert”, but she has few illusions. ‘After all these years I still cannot see if anyone is lying. Police officers who have followed specific lie detection training courses or behavioural scientists also score no better than someone who does not even listen to the story and simply throws up a coin. Truth or lie, 50 percent chance.’

Van der Zee relies more on technology to find out the truth. Together with her husband, she developed a new kind of lie detector. By means of a motion-capture suit, the movement of the person wearing it are accurately measured. On the screen a drawn man turns green, with a small stripe of red. ‘The colours indicate how much someone moves. Red means more movement, and is usually an indication of lying. Four out of five people move more when they lie, one out of five less. That has confused interrogators. For a long time they thought that many fiddling or turning away the head were signs of dishonesty. But it is more complex. It does seem that moving more or less during lying is stable per person. So, we could continue with that, and investigate the changes in movement patterns. So far our results are promising.’

Last year Van der Zee participated in the BBC documentary A Week without Lying, which showed three people that promised to speak the truth for a week. Van der Zee was surprised at how deeply lying is imbedded in our society and ourselves. ‘People are so dishonest. Much more than they think. No matter how hard they tried, all three participants lied several times during that week. One of them erupted into tears hallway through, as she came to the conclusion that she was much more dishonest than she first thought.

According to Van der Zee, it depends on three factors how strongly we feel about the fact that someone else has lied to us: who, why and what. ‘We think it is worse when someone close to us lies to us. Intent also plays a major role: did the lie serve the liar or someone else? Those who lie for self-interest can count on less understanding. And then there is the question of whether the lie had an emotional, financial or material motive.’

The entire article in De Standaard can be downloaded below, 23 March 2019 (in Dutch).

Assistant professor
Faculty
Erasmus School of Economics
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Earlier news articles about Van der Zee’s research can be found here and here.