What does it mean to devote yourself wholly to helping others? In Strangers Drowning , Larissa MacFarquhar seeks out people living lives of extreme ethical commitment and tells their deeply intimate stories; their stubborn integrity and their compromises; their bravery and their recklessness; their joys and defeats and wrenching dilemmas. A couple adopts two children in distress. But then they think: If they can change two lives, why not four? Or...