This Korean parenting style is the best-kept secret to raising smart and successful kids

One of the first words I learned as a child was "nunchi" (pronounced noon-chee), which literally translates as "eye-measure."

Nunchi is the art of sensing what other people are thinking and feeling — and then responding appropriately. It's the ability to quickly read a room with the emphasis on the collective, not on specific individuals.

Speed is paramount to nunchi. Those who have "quick" nunchi continuously recalibrate their assumptions based on any new word, gesture or facial expression, so that they're always present and aware.

In Korea, nunchi is a superpower. Some even go as far as to say it allows you to read minds, though there's nothing supernatural about it. A well-honed and quick nunchi can help you choose the right partner in life or business, shine at work, protect you against those who mean you harm and even reduce social anxiety.

It's easy to confuse nunchi with empathy, but having too much empathy can be destabilizing. Nunchi, on the other hand, puts quiet observation first; it allows you to stay on firm ground while still listening to the other person.

To harness the power of nunchi, all you need are your eyes and ears. And the hardest part: a quiet mind.

In traditional Korean child-rearing, nunchi is on a par with "Look both ways before crossing the street" and "Don't hit your sister." Parents teach their kids about nunchi starting as early as the age of three. (The tradition follows a well-known expression that goes: "A habit formed at age three lasts until age 80.")

"Why do you have no nunchi?!" is a common parental chastisement. As a child, I remember having accidentally offended a family friend, and defending myself to my father by saying, "I didn't mean to upset Jinny's mother!" To which my father replied, "The fact that the harm wasn't intentional doesn't make it better. It actually makes it worse."

Some Westerners might find my father's criticism difficult to understand. Wouldn't you prefer your child to be mean accidentally, rather than deliberately?

But here's another way to think about it: Children who choose to be mean at least know what they hope to achieve by it, whether it's getting even with a sibling or getting a rise out of a parent.

A child who is unaware of the consequences that their actions or words have on other people, however, is a child with no nunchi. And no matter how sweet and kind they are, they're likely to be on the losing end of life — unless that cluelessness is trained out of them.

Korean parents instill nunchi by first teaching their children this crucial lesson: "It's not all about you."

I'm not a parent. But I can attest to the immeasurable value of being raised on this wisdom. Let's say a mother and her four-year-old son have been waiting at a buffet line for a long time, and the son starts to get impatient.

"We've been here forever! I'm hungry!" the son complains. A Korean mother won't respond with, "Oh, you poor thing! I'm sorry. Here, I have some grapes in my purse that can hold you over." Instead, she'll say, "Take a look at everyone else waiting in line, just like you. Now do you think you're the only person in this queue who is hungry?"

This type of upbringing is meant to teach children that the world doesn't revolve around them, and that things don't get handed to them on a silver platter.

Another example: Some schools in Korea don't employ janitors. Students are expected to take turns cleaning — sweeping, mopping, taking out trash and even cleaning bathrooms. Everyone is divided into groups and responsibilities are rotated.

There are several lessons here. For one, the tidier you are, the less time time it will take to clean up. Another is to instill an awareness of the entire class as a single hive. The students must respect their environment as a team, because they're the ones responsible for preserving it.

Some are born with nunchi, some achieve nunchi and some have nunchi thrust upon them.

I had it thrust upon me. When I was 12, my family moved from America back to their homeland, South Korea. Despite only speaking English, I was enrolled into a Korean public school.

This was the best nunchi crash course I could have asked for, because I had to assimilate into a foreign culture with zero linguistic clues. In order to succeed in my new country, I had to be hyper-reliant on my nunchi, which ultimately became my sixth sense.

In my day, students weren't allowed to ask questions during class. Teachers intentionally gave vague information about everything from where exams were taking place to what supplies or books to bring. Working out these mysteries on your own by using nunchi was part of your education.

This is how I learned one of the cardinal rules of nunchi: If you can observe with patience, then your questions — what to do, how to act, how to respond — will be answered without your having to say a word.

Just over a year after arriving in Korea, I was at the top of my class and a prize-winning math and physics student. Within 18 months, I was elected vice president of my class. I achieved all of this despite the fact that my Korean was still pretty terrible.

To those who are still skeptical about the power of nunchi: I am living proof that you don't need to be the smartest, richest or most privileged person to find success and happiness in life; you only need to have quick nunchi.

Euny Hong is a journalist and author of "The Power of Nunchi: The Korean Secret to Happiness and Success" (Penguin Books). Her work has appeared in The New York Times, The Financial Times, The Washington Post, The Wall Street Journal and The Boston Globe. Euny graduated from Yale University with a B.A. in philosophy and is a former Fulbright Scholar.

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