It seems like famous people make headlines for lying almost every day. But we all lie. Lying may even distinguish human language from the communication systems of other animals.

A dog, for example, snarls and snaps as a warning. It’s not teasing or boasting about biting. You ignore its warning at your peril. But language allows false statements. Even 2-year-old children lie! Their falsehoods tend to be obvious. (e.g., “I didn’t look.”) And we get better at lying as we age.

Check some definitions of the verb “to lie” and you’ll find that the intent to deceive is central. But we deceive each other for many reasons, including reasons that are good, or at least not evil. For example, we lie to improve social interactions. I owe my spouse an apology, and I whine: “I had a headache — I didn’t mean to insult you.” (At the time, I certainly did mean it.)

Another reason we often appear untruthful is that memory is vulnerable. As cognitive psychologist Elizabeth Loftus documents, it isn’t just that we forget. We also remember falsely. Loftus starts a TED Talk by describing a rape victim reviewing a photo lineup. Pointing to one man’s photo, she said, “That one’s the closest.” At his trial later, she said: “I’m absolutely positive. That’s the man.” He was convicted and sentenced to prison. Then, an investigative journalist found the actual rapist.

Loftus compares changes in memory over time to Wikipedia: Our memories are constructed. We ourselves can go back in and edit them; so can other people. So memory itself also contributes to how accurately we talk about earlier events. It’s not just how honest or socially savvy we are.

Are we as good at catching lies as we are at lying? You’d think the two skills would synchronize in an evolutionary race between liars and truth tellers. TV shows like “Lie to Me” suggest that at least some people are good at detecting lies. Also, research in areas such as business and law enforcement finds many specific cues to lying. For example, truth tellers tend to use fewer words and simpler sentence structure than liars do.

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It turns out that we’re actually much better at telling than at detecting lies. If you’d like to learn more about this, go to truthaboutdeception.com. This website shares advanced research about lying to and cheating on people we love. The website’s articles are written by established scholars who make this scholarship accessible.

What else does lying research reveal? For one thing, research with children suggests that the evolutionary race isn’t over yet. While children lie, they also show strategic sensitivity to lying. Researchers at the University of Rochester invited children to do an art project. A child in the study’s “unreliable” environment waited while a researcher went to get appropriate supplies. The researcher returned empty-handed. This routine of unfulfilled promises was then repeated. A child in the “reliable” environment got the same routines except that the researcher brought the promised supplies both times.

After gauging the researcher’s reliability from these exchanges, each child participated in the marshmallow test of willpower: “You can eat one marshmallow now. Or, you can wait while I go get more, and then you can eat two marshmallows.” Watching from elsewhere, researchers and parents found that trust affected children’s marshmallow decisions. The average wait for children from the unreliable environment was less than 5 minutes but about 12 minutes for children from the reliable environment.

The prevalence of lying should make us more tolerant. And our faulty detection system might make us more cautious about believing.

Public Voices fellow Cecile McKee is associate dean for research and a professor of linguistics in the University of Arizona’s College of Social and Behavioral Sciences. Contact her at mckee@u.arizona.edu