We walk in the street, and strangers protect us, such as the police; Strangers put out our fire; Strangers educate our children; Strangers build our houses; When we travel by bus, train or plane, our lives are in the hands of strangers ... If we are sick and stay in the hospital, strangers will cut our bodies, clean us, take care of us, kill us or cure us. If we die, strangers will bury us.
Accepting strangers is a force for kindness, and the reconstruction of social trust system will sprout from the release of goodwill to strangers. Although the "Bao Tuan" movement, which is popular all over the world, is somewhat artificial, it has already revealed this sign-the acceptance of "strangers" is a higher civilized scale.
I suggest you go online and search Feng Huan's "We Always Depend on the Kindness of Strangers". It's well written, I hope it will help you!