Book excerpt: With examples ranging from timbering and fishing to automobility and meat production, Princen shows that sufficiency is perfectly sensible and yet absolutely contrary to modern society's dominant principle, efficiency. He argues that seeking enough when more is possible is both intuitive and rational - personally, organisationally and ecologically rational. And under global ecological constraint, it is ethical. Over the long term, an economy - indeed a society--cannot operate as if there's never enough and never too much.