article_snippet.sent: Yet on a finite Earth, with a billion new people being added every 15 years, that juggernaut is now laying siege to the physical bases of life and the social support systems that make life pleasant and decent.  
article_snippet.sent: And in some sense, there's a lot to say for the theory.  
article_snippet.sent: Novelists, ethicists, activists, unionists, preachers, teachers, and others have long known these facts, but the juggernaut has proved hard to tame.