A ballet dancer leaves her purse on a park bench. She walks away, absent-mindedly leaving behind the little bag with her money and belongings in it. Fifteen minutes later, she realises it's missing. She does not panic; she does not get that sick feeling in the pit of her stomach. She knows it will be exactly where she left it, untouched. Sure enough, upon retracing her steps, she finds the purse and cheerfully picks it up.

Riddle me this: If a ballet dancer is this lackadaisical about her belongings, where in the world does she live?

Finland. Minna Tervamäki lives in Finland.

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"I feel safe here. I feel for sure one of the main things people feel in Finland is safe," said Tervamäki, who was nominated as the most positive person in Finland last year by a company called Positiivarit Oy, which make products to encourage positive thinking. "We trust each other."

According to the 2018 World Happiness Report, based on research conducted by Gallup, Finland is the happiest country in the world. The Finns are not so sure about the result, though - being, as they are, a typically stoic sort of people.

"Nordic people, and the Finns in particular, are emotionally introverted," explained Meik Wiking, CEO of the Happiness Research Institute, an independent think tank in Denmark that studies happiness and wellbeing. "They rarely rank highly on expressions of joy or anger - they are very different in that way from people from Latin America, for example, who have a more exuberant emotional expression as a people. For [the Finns], happiness is more about living a reserved, balanced and resilient life."

Tervamäki agrees, saying, "I have very contradictory feelings about the happiness survey. Finnish people read it and laugh, like 'What? Us?'. What comes to my mind is that Finnish people are content more than happy."

The discrepancy comes from the fact that the happiness study is, paradoxically, not actually about our most coveted emotion: happiness. Professor Emeritus John Helliwell of the University of British Columbia, co-editor of the World Happiness Report, explains that measuring happiness is not an emotional study at all - in fact, it has a lot more to do with Tervamäki's purse. It is, rather, a look at the quality of life around the world, and in those terms, Finland came out the strongest this year.

"The factors that contribute to quality of life are a healthy life expectancy and a strong GDP per capita," Helliwell said. "But also things like being capable of looking after one another, having someone to count on in times of trouble, the freedom to make your own life decisions and personal support. It's about trust and generosity, and Finland ranks very high in those. Nordic countries tend to have a flatter structure in their society, less inequality, and a better capacity to help the disadvantaged. All of these things would make them score higher on a test which asks them to rank their quality of life."

For the Finns, happiness is more about living a reserved, balanced and resilient life

Dr Frank Martela, a researcher in social psychology at the University of Helsinki, agrees. "Trust is a big thing here. People want to see themselves as trustworthy. If you drop your wallet on the street, you can be quite sure you get it back - usually with the money still inside. Reader's Digest actually tested this once. Of all the cities they studied, most wallets were returned in Helsinki. No wonder then, that of all European countries, trust in strangers is highest in Finland."

This year, for the first time, the World Happiness Report asked immigrants to take part in the survey, and the happiness of the immigrant populations were virtually identical to the results for the overall population, with Finland at the top. That is to say, both Finnish-born people and those who migrated there are equally happy. This is interesting because it essentially refutes the theory that happiness is intrinsically Finnish.  

"Looking at immigrants' happiness shatters the idea that Nordic countries are closed, homogenic societies," Helliwell said. "If happiness is to do with something in the Finnish psyche, it's equally available to someone from Bangladesh. So it's got to be more about the way the country is run."

Finland is governed with efficient compassion and a profound respect for human rights. It's one of the best places in the world to be a mother and has one of the world's best education systems. It is astoundingly good at environmental policy, gender equality and work-life balance. These are all things that can make a nation of people demonstrably more content with their lives than any other, whether or not it's in their nature or their culture to smile about it. It is indeed quite possible to be outwardly grouchy - and still live in the 'happiest' place on Earth.

"If Finns tell you they're not happy, I understand," said Finland native Anu Partanen, author of The Nordic Theory of Everything: In Search of a Better Life, who has lived in the US for a decade but plans to move her family back this summer. "They are often pessimistic by nature and reserved about their emotions. They drink too much, it's dark, the winters are cold and hard psychologically. This Finnish happiness we hear about is not about dancing or smiling or being outwardly happy. If that's your idea of happy, then no, they are not the happiest. These studies are about the quality of life, that's why. Of all possible lives, are you living the best one? Can you control your life? Do you have choices? Can you spend time with your family? Do you feel safe? Can you be productive in society?"

(And, perhaps worth asking too: can you get drunk in your pants at home and call it a national tradition? The best trend since hygge is päntsdrunk, the English version of the Finnish word kalsarikänni, which means sitting at home, alone, drinking in your underwear.)

The emotional repression or introversion that Finns can be known for may have to do with something called 'sisu'. Sisu is a Finnish word meaning a show of strength, stoicism and resilience - and it's an important part of the Finnish identity. Part of the reason Finnish people do not, idiosyncratically and generally speaking, tend to display a lot of intense emotion is because they value a quiet courage and patience over outlandish joy - and perhaps that is why they are so confused to be crowned happiest population.

"I understand why the Finns might say 'Really? Us?' The Danes and the Norwegians have the same reaction," Wiking said. "People forget that what it is we're measuring when we do happiness research and they forget that it's a national average. It's probably more accurate to say that the Finns are the least unhappy people in the world. They always do well at reducing the causes of unhappiness. Things like financial stress, barriers to accessing healthcare and homelessness - things that make us unhappy. They are simply better at converting wealth into wellbeing."

When these happiness evaluations are released, Wiking says there is always a great deal of curiosity about the top-ranked nations. We are naturally fascinated by people who seem to achieve happiness, this great emotional state we all aspire to, and even more so by the idea of an entire nation of people who live in glee. There are fewer questions asked about the nations on the bottom of the happiness list - places like Syria, Liberia and Afghanistan - because unhappiness is obvious. If we believe there is some sort of secret to Finnish happiness, perhaps the closest thing is to live in a society that emphatically values trust and generosity.

"When these studies come out, everyone says 'Want to be happy? Move to Finland.' We can't all fit in the happiest place; they'd no longer be the happiest if everyone came for their dose," Helliwell said. "The moral of these studies is more: how do we do what they do, what do the Finns do right, how can we make better lives for ourselves and other people? Those are the questions we should be asking. As for the Finns, they should just relax a bit more and enjoy their happiness."

Why We Are What We Are is a BBC Travel series examining the characteristics of a country and investigating whether they are true.

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