Are you a good liar? Experimental psychologist Richard Wiseman has devised a quick test to figure out whether someone has a propensity to be a good liar. It involves no equipment and very little effort on your part. If you have a finger and know how to write a capital letter “Q,” it’s pretty simple.

Why do people lie?

Whether you like it or not, everyone lies. Some people lie on occasion. Others lie all the time. A study published in the Journal of Personality and Social Psychology found that people lie in one in five of their daily interactions. Sometimes we engage in deceitful behavior without even knowing it. According to Psychology Today, people lie by telling only their side of a story, omitting key information, exaggerating things, and communicating covertly. In a 2003 article for The New York Times, Dr. Richard A. Friedman surmised that every lie a person tells has a psychological reason behind it. Some people lie to feel better about themselves, others do it to cope with harsh realities. And most of the time, people lie to protect themselves from the actions and opinions of other people.

“Most of us have mastered the skill of lying,” Friedman said. “And lies, like secrets, are rarely as interesting as the psychological reasons behind them.”

Richard Wiseman’s “Q” test for lying

In a short YouTube video, Wiseman goes through the steps of determining whether a person is a good liar. First, take the index finger of your dominant hand and draw a capital Q on your forehead. If you draw the Q in a way that could be easily read by someone facing you, with the tail facing the left side, Wiseman says you’re probably a pretty good liar. That’s because you like being the center of attention and do things with other people’s opinions in mind.

If you draw the Q with the tail facing the right side, you’re probably not a great liar, according to Wiseman. People who draw the tail where only they can see it care less about other people’s opinions and, therefore, are probably not as good at lying.

For more of Wiseman’s simple life tests, you can purchase his book, 59 Seconds: Change Your Life in Under a Minute.

Source: DePaulo, BM, Kashy DA. Lying in everyday life. Journal of Personality and Social Psychology. 1996.