人口論
In An Essay on the Principle of Population Malthus argues for the reining in of rising population through 2 checks: Positive and Preventive checks. The first raising death rates, the later lowers birthing rates. Malthus also brings forth the idea that the world population will move past the sustainable number of people. This form of thought still continues to influences debates on birth and marriage rates to this theory brought forth by Malthus. The essay had a major influence on Charles Darwin and helped him to theories his theory of Natural Selection. This struggle proposed by Malthusian thought not only influenced the ecological work of Charles Darwin, but helped bring about an economic theory of world of ecology.