"Starting about the late 1960s there have been increasing fears that economic growth would soon lead to the exhaustion of raw materials and, food supplies, or environmental damage of one kind or another. These fears have been accompanied by widespread appeal to the concept of sustainable development, of which there have been many definitions, most of which make very little sense. The most widespread definition is that it requires a development that enables per capita income levels to be maintained at some unspecified recent (or current?) level. The article discusses the weakness of this concept, particularly of its ethical foundations, as well as the impossibility of precise measurement. The most recent, and perhaps serious fear about the effects of economic growth is the possibility of climate change. For although the science of this is more controversial than is generally believed, the mere fact of uncertainty concerning future climate change means that provided the costs are not excessive some mitigation policy ought to be pursued. The case for this cannot, however, be established on the basis of the usual formal models of economics or on any clearly defined ethical system. And one needs to be wary of appeals to any policy to implement drastic and very costly measures to combat climate change, when these policies can reflect the interests of a wide variety of pressure groups, and when they could be at the expense of other policies to assist the poorest sections of the global community, whose urgent needs are here and now."
