Thomas Malthus

Thomas Malthus' An Essay on the Principle of Population was the key for both Darwin and Wallace in unlocking the mechanism of evolution: natural selection. Malthus' arguments are interesting today as a starting point for discussions about population. Using Malthus provides a direct tie to courses in political science and business.

Write an essay that explains the relationship between Malthus' statements, the new article-The Want of Feed-and the previous article about fishing down on the food chain. Due: Tuesday, April 21.

Mydans, Seth. 1998. "For want of feed, Indonesia is losing its chickens." New York Times, Friday, April 3, 1998. L A4.

BOGOOR, Indonesia--People are waiting to see which will go first, the chickens or the eggs. Either way, both foods may soon disappear from people's diets, heralding severe food shortages here in the world's fourth most-populous nation. Etc.

Stevens, William K. 1998. "Man moves down the marine food chain, creating havoc." Tuesday, February 10, 1998. F 3.

As overfishing depletes prized species like tuna, cod and swordfish, commercial fishermen are moving farther down oceanic food webs in search of a catch, a new study has found. If this quest is pursued to its logical end, scientists warn, it will lead to a wholesale collapse of marine ecosystems. Etc.

Malthus, Thomas Robert. 1976 [reprint of essay of 1798]. An essay on the principle of population. W. W. Norton & Co., New York. 260 pp.

[p. 19] I think I may fairly make two postulata. First, That food is necessary to the existence of man. Secondly, That the passion between the sexes is necessary and will remain nearly in its present state.
[p. 20] Assuming then, my postulata as granted, I say that the power of population is indefinitely greater than the power in the earth to produce subsistence for man.

Population, when unchecked, increases in a geometrical ration. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will show the immensity of the first power in comparison of the second. (p. 23: Taking the population of the world at any number, a thousand millions, for instance, the human species would increase in the ratio of-1, 2, 4, 8, 16, 32, 64, 128, 256, 512, &c. and subsistence as-1, 2, 3, 4, 5, 6, 7, 8, 9, 10, &c.)

This implies a strong and constantly operating check on population from the difficulty of subsistence. This difficulty must fall some where and must necessarily be severely felt by a large portion of mankind.

[p. 24] We will suppose the means of subsistence in any country just equal to the easy support of its inhabitants. The constant effort towards population, which is found to act even in the most vicious societies, increases the number of people before the means of subsistence are increased. The food therefore which before supported seven millions must now be divided among seven millions and a half or eight millions. The poor consequently must live much worse, and many of them be reduced to severe distress. The number of labourers also being above the proportion of the work in the market, the price of labour must tend toward a decrease, while the price of provisions would at the same time tend to rise. The labourer therefore must work harder to earn the same as he did before. During this season of distress, the discouragements to marriage and the difficulty of rearing a family are so great that population is at a stand. In the mean time the cheapness of labour, the plenty of labourers, and the necessity of an increased industry amongst them, encourage cultivators to employ more labour upon their land, to turn up fresh soil, and to manure and improve more completely what is already in tillage, till ultimately the means of subsistence become in the same proportion to the population as at the period from which we set out. The situation of the labourer being then again tolerably comfortable, the restraints to population are in some degree loosened, and the same retrograde and progressive movements with respect to happiness are repeated.

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Last updated 30 December 1998 (JHW)