The meaning of sustainability is the subject of intense debate among environmental and resourceeconomists. Perhaps no other issue separates more the traditional economic view of the naturalworld from the views of most natural scientists. The debate currently focuses on the...

The nature of energy and material resources in an endogenous growththeory framework is clarified. This involves three modifications of the conventional theory. Firstly, multiple feedback mechanisms or "growth engines" are identified. Secondly, a productionfunction distinguishesbetween resource...