Most people believe that they know what it means to be 'green'. But do they? This book explores what it means to live a 'green' life for an individual human, and what it means for the human species to be a 'green' species. The conclusion is a provocative one - that at the level of an individual human being 'green' is about the possession of a particular attitude to life and the universe, whilst at the level of the human species being 'green' is about the sustainability of the biosphere. This may sound like an obvious conclusion to reach, but it entails that high levels of human resource use and the development of increasingly complex human technologies are 'green' actions which are necessary for sustainability. So, if you believe that being 'green' is about minimising human impacts/minimising human resource use then prepare to have your beliefs challenged.