Modern industnalised co untn es use far greater quanbties per head of metals, water, petroleum, coal, and wood-produds than developing countries, much of it being imported from the developing countries. This is the natural consequence of the higher general standard of living in present-day industrialised countries. Even assuming that the population of developing countries remains fixed at present levels, it follows that, if the standard of living in these countries is to reach those of present-day industrialised countries, a considerable increase in production and hence considerably higher consumption of resources will be unavoidable. Which of the following, if true, would most weaken the above argument?