Some people when they have taken too much and have been driven beyond the point of endurance, simply crumble and give up. There are others, though they are not many, who will for some reason always be unconquerable. You meet them in time of war and also in time of peace. They have an indomitable spirit and nothing, neither pain nor torture nor threat of death, will cause them to give up.
Roald Dahl, The Wonderful Story of Henry Sugar and Six More
attitude, endurance, hero, motivational, not-giving-up, spirit