50 SOCIAL SCIENTIST Most of the proposals suggesting the use of renewable agricultural biomass and forests for the development of energy sources are retrograde. The use of agricultural wastes or the development of cultures designed to produce products rich in energy, sugar starch, oils, turpenes, which can be changed into petroleum substitutes, particularly into ethanol, reveal a total ignorance of agronomic realities. The fear of petroleum shortage and continuing irrational uses of petroleum has led many scientists in the capitalist world to propose the extension of such aberrations, even in countries which already suffer from them. The development of fast-growing energy plantations and the use of forests for methanol and burning are dangerous. The Brazilian government seeks to change the natural composition of the forests by planting 400,000 hectares of eucalyptus. On the opposite side of the globe, in Vietnam, the forest administration proposes to eliminate eucalyptus planted under the French because it degrades the soil. The degradation of soil in the tropics is more difficult to reverse than elsewhere. Is it not astonishing that a country with an inestimable hydraulic potential such as Brazil does not plan for the development of an electric railway system, but multiplies its motorways and transforms its agriculture and its forests into petrol pumps? Manioc of Brazil is used as an internal combustion fuel. So long as mankind cannot exist without plant photosynthesis, it has to keep the best of its soils for food production and not for energy products. Rationality depends on the objectives, and energy policy is an example. The Soviet Union long ago brought together the supply of combined power and heating in towns. The Soviet state did not hesitate to close down, transfer or completely wind up 700 enterprises and workshops from Moscow in a short period of time on ecological grounds. Already 55.8 per cent of water used in industry follows a closed cycle. In the development of transport, preference is being given to public transport as a matter of principle. It is true that the awareness is far greater now in the socialist countries compared to what it was earlier when the efforts of the Soviet Union were directed towards restoring the national economy damaged by war, providing shelter and food for millions of people and when, consequently, they had inevitably to limit the funds and labour force allocated to nature conservation. The use of capital-intensive technologies has not increased inequalities and created the problem of unemployment in the socialist countries as is the case in the advanced capitalist countries and in the Third World countries pursuing the path of capitalist development.