What’s sisu, you ask?

“Sisu is a Finnish term loosely translated as strength of will, determination, perseverance and acting rationally in the face of adversity. […] The word derives from sisus, which means something inner or interior. However sisu is defined by a long-term element in it; it is not momentary courage, but the ability to sustain an action against the odds. It is similar to equanimity, except the forbearance of sisuhas a grimmer quality of stress management than the latter. Deciding on a course of action and then sticking to that decision against repeated failures is sisu.”