Dhe dating partner cancels a dinner because he suddenly feels bad. Is the story true – or just made up because he might not have felt like meeting? Distinguishing between lies and truth is often difficult if not impossible. A simple rule of thumb could make it easier to uncover lies, as a recently published study from the Netherlands shows. It is: Less is more.
If you only pay attention to the level of detail in a story, liars are easier to expose, write scientists from Amsterdam, Maastricht and Tilburg im Journal “Nature Human Behaviour”.
“People who tell the truth can give a more informed description because they actually experienced the event,” explains Bruno Verschuere, professor of forensic psychology at the University of Amsterdam.
But let’s start from the beginning: Lying is human. Implementing the topic in research is not always easy, says Matthias Gamer. The professor of experimental clinical psychology at the University of Würzburg has been dealing with the subject of lies for around 20 years. “The problem with the question of how often you lie is: how do you find out?” he says. After all, you have to rely on people answering this question honestly – and not fibbing.
There is general agreement on what constitutes a lie, says Philipp Gerlach, Professor of General and Social Psychology at the Fresenius University of Applied Sciences in Hamburg. There is a kind of minimum consensus: “The intentional telling of an untruth with the aim of deceiving someone.” That means: A lie is always intentional and the liar wants to achieve something with it.
Lies can also be divided into two basic categories, such as “selfish” and “prosocial” lies, says Gamer. In English they are also called “black” and “white lies” – black and white lies. If someone gets stopped in their car by the police after a pub crawl and tells them, contrary to the truth, that they only had one beer, that is a selfish (black) lie. “These should help you or give you your own advantage,” says Gamer.
Prosocial—or white—lies, on the other hand, are meant to protect other people or do them a favor. For example, “My boyfriend or girlfriend is feeling really bad, and I tell him or her that the situation isn’t that bad, even though I know for a fact that it isn’t,” Gamer explains. But many lies lie between these two categories.
There can be various reasons why we sometimes don’t want to tell the truth to our counterpart. It depends on the situation, says social psychologist Gerlach. Some lie for altruistic reasons, to avoid hurting someone. For example, if your friend was having a bad hair day and comes in with a hairstyle that doesn’t suit her. “These are morally acceptable reasons.”
Even if it’s very simple and doesn’t have any major negative consequences for other people, lying tends to be easier, explains Gamer. At least some studies in which test subjects were asked to throw the dice several times in a row suggested this. Beforehand, they were told that they would get one euro for every six they rolled and that no one would watch their rolls.
At the end, each participant was allowed to say for themselves which numbers were on their dice. “In such situations, you can find a substantial proportion of lies, because it’s easy to say: I rolled four sixes, even though there were only two,” explains Gamer.
According to the expert, one thing is clear: “On the one hand we lie, and on the other hand we are bad at recognizing lies.” That has to do with evolution. Lying helps as a skill, for example to gain advantages for yourself. But in order for it to prevail, it must of course work. “It means that if we were all good at spotting lies, there would be no lies in the world.”
But how do we recognize a lie in everyday life when it is so difficult? According to the study from the Netherlands, at least the level of detail helps a lot. The research team had done a series of laboratory experiments for this. There, the 1,445 participants were asked to look at and rate handwritten statements, live interviews or video interviews: Are they true or lies?
In the study, the subjects were divided into different groups. One group could listen for all sorts of cues – for example, nervous behavior, how much eye contact people make, or how convincingly someone is telling their story. Another group should only pay attention to the amount of detail. Participants who only focused on details performed better at debunking a lie.
“What’s unique about this study is that if you don’t have a clue and you’re bad at spotting lies, the best thing to do is rely on a trait that has at least some level of accuracy,” says Gamer, der was not involved in the work.
That can also help in everyday life. For example, by asking our partner or child specific questions if we suspect a lie. Does he or she keep telling the same story with the similar details, is it logical? These could already be clues that point to the truth. However, details are no guarantee that liars will be regularly exposed. And: People could also take advantage of the knowledge and embellish their story next time, so as not to be exposed, gamers consider.
From the expert’s point of view, however, tips that can be found again and again on the Internet, such as “Liars look to the top right” or “Liars touch their noses”, should bring little success. These are simply myths – they have no meaning, says Gamer. Because: There is no scientific evidence that people actually behave differently when they make true or false statements.
A prominent example of this is the Lewinsky affair of former US President Bill Clinton. An extramarital relationship with then-intern Monica Lewinsky, which the president tried to hide, had led to an impeachment trial in 1998 on suspicion of perjury and obstruction of justice. A common assumption is that because Clinton touched his nose several times when questioned about Lewinksy, he gave himself away.
“There are actually people who say: The blood vessels in the nose dilate. The nose gets bigger at the moment of lying and that’s why it starts to itch. Of course, that also fits in perfectly with the Pinocchio story,” says Gamer. In this context, however, one does not take into account all the other interviews about Lewinksy, in which Clinton did not touch his nose once. Or people who tell the truth but just rub their noses.
Finding out the truth is often difficult. Jonas Schemmel knows that too. He is a statement psychologist. That is, he evaluates the credibility of witness statements during a criminal trial. Most of the time, testimony psychologists are used in particularly difficult procedures. For example, in the case of sex crimes, when there is no testimony other than that of the victim and no other evidence. Then there would just be one statement against another.
“It’s a highly complex task, especially for adults,” says Schemmel about the challenges of his job. Here, too, details played an important role. His assessments often last several hours, sometimes they take place several times. “We rely on the assumption that it is very complicated to make up a story in such a situation, to react spontaneously to questions and to avoid verifiable information,” explains Schemmel, who heads the Victimology research unit at the Criminological Research Institute in Lower Saxony.
People who tell the truth could refer to personal memories, give many different and unusual details. According to Schemmel, this probably speaks for a true statement. But: This method does not work the other way around: it does not automatically indicate a lie if someone gives a few details. In part, the event could have been a long time in the past or it was a brief encounter, says the statement psychologist: “Then there may not be much to say.”
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