Sisu is a Finnish concept that encompasses extraordinary determination in the face of extreme adversity, courage, resilience, and hardiness. It is often described as a unique Finnish quality that is not easily translated into English. Sisu is not just momentary courage, but the ability to sustain that courage and take action against the odds. It is an inherent characteristic of the Finnish people, representing the philosophy that what must be done will be done, regardless of the cost. Sisu can be roughly translated into English as strength of will, determination, perseverance, and acting rationally in the face of adversity