I grabbed Grit by Angela Duckworth at Oslo Airport to read on the plane. It's a book about what goes through your head when you fall down, and how that makes all the difference.
I found the chapter about culture particularly interesting. Finnish sisu is presented as an example of gritty identity. Finland seems to have forged a strong culture of grit.
Two powerful lessons can be extracted from Finnish sisu:
1. Thinking of yourself as someone who is able to overcome any adversity leads to behavior that confirms that self-conception.
2. It sometimes feels like we have nothing left to give, and yet if we keep on putting one foot in front of the other there is a way to accomplish what reason seems to argue against.
Could grit be the secret to success? According to this book yes, grit can be more important than talent or luck. But now it's not a secret anymore.