Warren Buffett says this quick mental exercise will make you a happier person

Warren Buffett
Adam Jeffery | CNBC

Warren Buffett is one of the richest men in the world, worth over $75 billion. If money could buy happiness, he could certainly afford it.

But when MBA students at the Ivey Business School at Western University asked Buffett "Are you happy?" his response had nothing to do with money.

"I get to do what I like to do with people that I love," Buffett answered during the 2008 talk. "That is happiness. I am happy day after day after day. How could I be any happier?"

If you're feeling less excited about life than he is, here's a quick exercise that Buffett suggested to the students — that you also can use — as a way to remedy the situation. (Appropriately for Buffett, the exercise uses the stock market as an analogy.)

Here's how it works: First, imagine the people in your life as publicly traded companies — some will succeed and their value will rise, some will flounder and watch their value fall.

"Imagine that I am going to give you an hour, and in that hour, you have to pick one of your classmates to own 10 percent of for the rest of your life," Buffett said.

"Then, when you write that person's name down, I will ask you to list the reasons or qualities that caused you to pick that person." Look for someone you predict will keep gaining value, who you would "buy long," according to Buffett.

Next, Buffett says think about someone who you would "sell short," which means you expect their value to decrease.

Consider the behaviors of the two people you picked and make a list.

"On the one side, you list the qualities of the person who you want to own 10 percent of, and on the other side you list the qualities of the person who you want to short 10 percent of," Buffett said.

When it comes to the person you expect to succeed, "You will find that these are not things you are born with, like the ability to kick a football or sing a high C; they are qualities that you actually generate for yourself," he says. "These are things like generosity, humor, forgiveness — all of the qualities that you admire in other people."

On the other side of the list, "Look at the qualities which turn you off in other people," Buffett said. "If they turn you off of other people — if you have them — you will turn people off of you. Those qualities, you don't have to have. You can get rid of them.

"The thing to do is look at that list and say, 'I want to be like the one I want to own 10 percent of,'" he says. Work on developing the personality of people you admire, while ridding yourself of the qualities you dislike in others.

For Buffett, it works: "The person that does that will be someone that is happy, I guarantee you."

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