The world runs so much better on trust. Unfortunately, according to a 1990s study in the Journal of Personality and Social Psychology, the average human tells up to two lies a day, Yet try as we might, no one can tell for sure when someone is lying.
Not that we haven’t tried. Psychologist William Moulton Marston, creator of the comic book character Wonder Woman, has also been credited with the invention of an early prototype of the Polygraph Machine, more commonly known as the Lie Detector (https://en.wikipedia.org/wiki/William_Moulton_Marston).
The Polygraph has been discredited as unreliable. But we’ve always looked for ways to detect untruthfulness. An extreme example is a medical case in 1993 of a 51-year-old Frenchman who, when he told lies, regularly lost consciousness and suffered convulsions. Then his doctors found a 30mm brain tumor which presumably triggered a rare form of epilepsy by agitating his brain’s limbic lobe.
Down through history, various civilizations have tried to develop their own lie-detection methods. The ancient Chinese forced suspects to chew a handful of raw rice, and, if they spat it out dry, they were considered guilty, presumably because fear and guilt dries up saliva.
If that isn’t bizarre enough, in ancient India suspects stood in a dark tent and were told to pull on the sooty tail of a sacred ass, which supposedly would bray loudly for the guilty. And if they had clean hands upon exiting, they were considered guilty because they’d been afraid to pull the tail. Damned if you do, and …
Since those early attempts, we have at least tried to become more sophisticated. One lie-detection way is to look for non-verbal clues, like someone who always looks at the floor, or verbal hints, like saying they don’t recall details. Story inconsistencies are another clue.
But despite all these methods, the sad truth is there is no sure way to catch a liar.
For more information, see “Can You Really Tell if Someone is Lying? Here’s What the Experts Say” at https://www.nationalgeographic.com/magazine/article/physical-signs-of-lying?