Kang Lee : Can you really tell if a kid is lying?

Kang Lee at TED 2016
Can you really tell if a kid is lying? (transcript)
Summary
Adults must believe that children start to tell lies after entering elementary school and they are poor liars. And if children lie very young age, they will be pathological liars for life.

However, the speaker tells us that those are wrong.

Some children can start lie when they are at two years of age, adults can't detect their lies. Children are not poor liars. They have abilities that are mind reading and self-control. Mind reading is that children know that you don't know what they know and self-control is that children control their speech, facial expression, and body language. Those two abilities are essential for all of us to function well in our society, thus children don't have them is serious developmental problems.

What would you do after you detect someone's lies?

The speaker said in the talk, still the study that transdermal optical imaging technology detects lies of people is an early stage of development, but it must be used to reveal politicians' or your girlfriends'/ boyfriends' emotions whether they lie or not in the near future. However, lying will never be the same.

However,  I would do the same thing even if I could detect someone's lies.

Words in this story
detect /verb/ discover or identify the presence or existence of.
lie, lay, lain, lying, lies /verb/ (of a person or animal) be in or assume a horizontal or resting position on a supporting surface. the man lay face downward on the grass.
lie, lied, lied. lying /verb/ deceive, cheat
lie, lies /noun/  falsehood, incorrect fact, or position, location, place
lay, laid, laid /verb/ put down, especially gently or carefully. she laid the baby in his crib.