chapter  5
Change within limits
Pages 30

This statement is significant because of the conceptual framework which underpins it and which typifies green economy discourse. It is the long-standing idea that environmental impact is the resultant of three factors, namely population growth, affluence and technology, expressed in the famous I = PAT formula (Ehrlich and Holdren 1971). Bluntly put, this equation states that total environmental impact (Impact) is equal to the number of people (Population) multiplied by the wealth per person (Affluence) – which is usually equated with the average consumption per person – multiplied by a technology factor (Technology).