Why would anyone ever risk one's life for ? one's country or a cause just to help other people, people that we don't know and probably will never know?

为什么人人都要为自己的国家或者,去救人的缘由而冒险，并且这个人我们不认识,可能永远也不会认识？

耶鲁公开课 - 政治哲学导论课程节选