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True or False? Check With Your Subconscious


Our brains seem designed to know when someone is telling the truth or not.

The brain is a wonderful organ for lots of reasons. But among the reasons you’re least likely to suspect, it’s also a reliable lie detector. A study led by psychologist Leanne ten Brinke at the University of California suggests that the attention we pay to people to discern whether or not they’re lying could also be a sophisticated way of deceiving ourselves. “Deep down” we can always detect signs of falsehoods when they’re presented to us.

The study began with the premise that humans appear to be easily misled because other studies designed to measure such ability have shown subjects are only able to detect 54% of lies. This is the equivalent of “guessing” as to whether someone’s lying or not because there are only two possibilities: the truth or a lie. But there are supposed to be clear indicators of body language to know when someone is lying, right? The direction of the look and the hands, the position of the body, the speed when speaking…, imagine for a moment that these are the parameters that a magician uses while performing a card trick: he looks at us instead of at the cards. These he shuffles quickly with urgent gestures, or while moving three identical cups under which he’s hidden a ball. The magician succeeds in “cheating” us as part of the trick. But is the trick in daily life rather that we decide to deceive ourselves in believing that the other is indeed speaking the truth?

The researchers’ hypothesis was that the unconscious mind could detect a liar even when the conscious mind couldn’t. Several tests included 72 participants who watched videos about suspects who’d taken a $100 bill from a ledge, along with videos about people who’d not taken the money. All of the interviewees in the videos said that they’d not taken the money, and some were thus necessarily lying. Others were necessarily telling the truth. The result was that participants detected 43% of liars and 48% of those telling the truth.

During the interviews, researchers also measured instinctive reactions in the eyes and gestures of the interviewees. They also sought to associate these movements with the appearance of words related to falsehoods such as “deceit” or “dishonest” and with words associated with the truth, such as “valid” and “honest.” The results suggest that participants reacted in a manner consistent with the truths or lies they heard, regardless of whether they consciously knew whether the person in the video was telling the truth or not.

For ten Brinke, “these results provide a new lens through which to examine social perception, and suggest that – at least in terms of the detection of lies – unconscious measures may provide additional insight into interpersonal accuracy.”

Videos and other information from the experiment are available online.  But a slightly more philosophical interpretation might suggest that it’s actually we who lie because somehow we need the words of the other to acquire the category of truth. It may be that human communication is based on the confidence we can place in the accuracy of the words and intentions of the other. Thus we’re made such that we trust more than we distrust, to the degree that we’re capable of being deceived. As Nietzsche pointed out that man is the only animal who lies, we might add that man is the only animal that is fooled, because unconsciously we always know when we’re being lied to.

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