Grim determination, indeed...

The Finnish way of life is summed up in “sisu,” a trait said to be part of the national character. The word roughly translates to “grim determination in the face of hardships", such as the country’s long winters.
Even in adversity, a Finn is expected to persevere, without complaining.
Back in the day when it wasn’t that easy to survive the winter, people had to struggle, and then it’s kind of been passed along the generations,” 
Our parents were this way. Our grandparents were this way. Tough and not worrying about everything. Just living life.”
~ Matias From, age 18, finnish citizen, in a NYT article on Finnish happiness