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How to Spot a Lie

A method so simple you could learn it from a toddler.

Vlasov Pavel/Shutterstock
Source: Vlasov Pavel/Shutterstock

Humans are primates and, therefore, social creatures. We generally prefer to mate, hang out in groups, and share experiences. Our brains are highly evolved to decode subtle facial expressions and understand complex speech. You can see evidence of our communal nature everywhere—families, sports teams, classrooms, restaurants. We like to do virtually everything together.

Even lie.

Lies come in all shapes and sizes. Some forms of dishonesty are major, such as marital infidelity or embezzling funds from work. Others, though, are of the “white lie” variety and include complimenting a friend on her dress even though you think it makes her look like an Oscar statuette.

But have you ever stopped to consider why we lie?

We typically think of lying in black-and-white moral terms, but there is more to the story. To be sure, people lie in an effort to maximize their own gain. We might lie about the amount of money we have (if we are trying to bargain for a good deal), how much we enjoyed a movie (if we are trying to win the favor of a date), or the amount of effort we put into a project (if we are trying to impress a boss). In many cases, stretching the truth din these ways doesn’t feel like a bold violation of our moral code precisely because we, ourselves, are the direct beneficiaries.

There are other reasons people lie: We are inclined toward dishonesty when we are tired, or when we are in the company of others. When fatigue sets in, lying can be a way of saving energy or other resources. Ever pretended to reach your allotment of push-ups by fudging the number a bit during a workout? We're also are more likely to lie when others around us do.

Lying, like many social phenomena, is contagious.

Interestingly, as common as lying is, we have also evolved fairly sophisticated mechanisms for “lie detection,” as psychologists fancifully call it. The phrase evokes all sorts of detective television dramas and Las Vegas card shark films based on the idea that anyone can learn how to spot a liar. Common lore holds that dishonest people look away when they lie, or that bluffers at the poker table fiddle with a ring or exhibit some similar “tell” that gives away their true mental state.

In a recent series of studies, though, participants succeeded at detecting lies no better than they would through guessing.

Infants, however, can detect one particular type of lie—emotional dishonesty. Because young children are preverbal and lack the life experience to recognize verbal lies, researchers turn to their understanding of feelings. In a recent study, Eric Walle examined the ability of 16- and 19-month-olds to recognize honest emotion. Like the best researchers in psychology, Walle appears to have had a blast in his process of making parents either hit or miss their own hand with a plastic hammer and then react with either put-on or authentic emotions. In a second study, parents were instructed to show either authentic or exaggerated fear. It turned out that 16-month-old children could not detect emotional artifice while 19-month-olds could. The latter group was able to pick up on whether feelings were appropriate to the context, appropriate in their intensity, and whether they were displayed appropriately.

Somewhere in that second year, we learn to spot fake.

What do toddlers and plastic hammers have to do with you and your marriage, your friendships, or your work? Lots. Rather than trying to play a TV psychic with an uncanny ability to deduce information based on belt buckles, wedding rings, and facial tics, just try being human. You can use yourself as an “emotional barometer” by paying attention to how you feel when someone talks to you. A recent study by Leanne ten Brinke and her colleagues showed that while people could only guess liars at chance (actually, worse than chance—43 percent), their accuracy improved when they went with their gut. Using computer reaction time tests that measure non-conscious attitudes, participants were more likely to pair deceit-related words with liars and honesty-related words with truth tellers. In fact, their accuracy improved significantly.

A gut feeling probably isn’t enough to take someone to court or to openly accuse a co-worker. An instinct about honesty is, however, enough to duck out on a dodgy date or to confront a friend or lover. Your hunches may not always be correct, but they may be correct enough of the time that they become a useful lie detector.

Dr. Robert Biswas-Diener is a research and trainer. More about the drawbacks and benefits of lying can be found in his book, co-authored with Dr. Todd Kashdan, The Upside of Your Dark Side: Why Being Your Whole Self—Not Just Your “Good” Self—Drives Success and Fulfillment, is available from Amazon, Barnes & Noble, Booksamillion, Powell's, or Indie Bound.