"All other elil do what they have to do and Frith moves them as he moves us. They live on the earth and they need food. Men will never rest till they've spoiled the earth and destroyed the animals."
Holly has just begun telling the story of the way the men poisoned their old warren. What he expresses is a sentiment found in several other places in the novel: the idea that men are capable of an evil the likes of which cannot be found anywhere else in nature. Other animals, even the elil who hunt rabbits, simply do what they need to do to survive. Rabbits may not want to be killed by stoats, but the stoats only want to kill the rabbits to eat, and they never kill more than they need. Men, on the other hand, rarely kill to eat and much more frequently kill for other reasons. Furthermore, they almost always kill more than they need. Holly is convinced that men will not stop until they have destroyed all of the animals. This passage is part of a plea on Adams's part to stop our destruction of the environment.