If a selfish person can get through field survival, it's not hard enough. (not that I'm going to find out, mind you. I abhor strenuous exercise and uncomfortableness.)
This. There are things that I would never do for money or for my own benefit that I would do willingly for family and friends. My teammates would be in this category with F&F. A commitment to someone or something higher and nobler that my own selfish interests will enable me to do things and achieve things that would otherwise be unachievable.
this..... i would eat anything, drag myself elbow over elbow, crawl, etc to get back alive to my PipSqueak and Miss Copper Kitties....