The United Nations Commission on Sustainable Development has identified four aspects of sustainable development: social, economic, environmental and institutional. In this paper the environmental aspect of sustainability will be of primary concern. .
# Ancient Problems of Sustainability.
The first problems in dealing with the environment - which one would now qualify as sustainability problems - occurred in Mesopotamia. The dangers inherent in the delicate irrigation system that was used there ultimately caused its collapse. Processes such as accretion and salination (which particularly affected the topsoil and, consequently, also the roots of crops growing there) eventually caused insurmountable difficulties. The decrease in yields could not be compensated by switching to other species of plant that were less salt-sensitive. Even though the Mesopotamian culture existed for approximately two thousand years, the seeds of its destruction were already sown when the system was created. In a certain sense, its 'intrinsic sustainability' was therefore not very great. .
In Greek antiquity, philosophers such as Plato (400 BC) and his student Aristotle (384 BC) discussed man's place in nature and his role in the depletion of the natural system. Plato pointed out that the forests in Attica were disappearing as a result of human intervention and that this had serious consequences for the people living there. He also paid attention to the size o the population, the availability of natural resources and the total area of fertile land. To all this, Aristotle added a strong sense of nature's usefulness. The idea that everything that happens in nature has a purpose and that man is the ultimate goal in the natural order has influenced ideas up to today. In Roman tins, Strabo and Pliny the Elder were among those who mentioned cases of improper use of raw materials and the disappearance of forests. The latter was a recurrent theme in the writing of that time.