You have applied for a university place or a job. They have invited you for a Zoom interview. It is all going well - that's until they ask you about that section of your application where you slightly exaggerated your skills. You quickly improvise an answer and you think you got away with it. But suddenly the screen lights up red and the word "lie" flashes across it.

This is the future promised by new software developed by researchers at Tel Aviv UniversityThe largest university in Israel, based in the city of Tel Aviv.. They claim that when we lie, there are slight twitches in our eyebrows or lips that give us away. By observing these ticsTwitches, movements or sounds that people do repeatedly. They happen involuntarily and often without the person even knowing what they are doing., their technology can detect 73% of lies.

Lying, and determining when someone is lying, can be a matter of life and death. So it is no wonder humans have been working on methods of lie detection for millennia. In ancient Rome, a suspect would be forced to put their hands in the Bocca della VeritaA large marble disk in the shape of the face of the god Oceanus in Rome. Its name means mouth of the truth., a marble disc in the shape of a head. If it were true, they would be able to withdraw the hand; if they were lying, it would be bitten off.

Long before then, China had come up with its own method. The suspect's mouth would be filled with rice as they repeated their statement. If the rice came out dry, they were assumed to be lying, because the anxiety would have caused their mouth to dry up.

Today, traditional polygraph tests look for changes in blood pressureThe beating of our hearts keeps our blood at a certain pressure. This pressure can rise when we are stressed, as the heart beats faster., pulseMomentary expansion of the arteries as blood is pumped through them. Like blood pressure, it can be used to tell when our heart is beating faster. and breathing for signs that the person being tested is nervous, which suggests they are lying.

But they are easy to cheat if you can just control your nerves. The new software is a more sophisticated version of the same thing, observing minute changes in your face that are beyond your control.

Some are worried about the implications of this. They argue that the world runs on white lies. If we cannot hide bits of the truth some of the time, then we will constantly be offending other people, and giving away things about ourselves that they can use against us. 

But others think software like this could be a huge advantage. Imagine if every time a politician gave a speech, your TV could tell you whether or not they are lying.

They point out how stressful it can be not knowing what others think of us. Because of white lies, we can never be sure whether or not compliments are sincere. If we all told the truth all the time, we might say more hurtful things, but we would not have to worry whether or not people really do like us.

On the other hand, perhaps this is all based on a simple misunderstanding of what lying actually means. People rarely actually lie outright, because it is too easy to get caught. But there are many ways of deceiving someone. As well as lying, we can leave out key information that they need to make a sound judgement.

Sometimes we make generalisations or say things with a level of confidence that we later regret. These are not lies, exactly, but they are the cause of most misunderstandings.

Yes: Most people lie as many as three times every ten minutes. We have to be able to conceal information from each other to protect ourselves and others from harm.

No: We spend so much of our time worrying about what people "really" think of us. Perhaps if we were more honest about our opinions, we could be more certain of this, and lead happier and less stressful lives.

Or... Not everything can be neatly divided into truths and lies. The best way of lying is often to tell a half-truth. We should stop putting our faith in technology to tell the difference between the two.