a Malthusian crisis is a situation in which the population in a given area has exceeded its food supply and therefore mass starvation results. This lowers the population and the cycle continues until the population and its food supply are once again in balance.
In modern times the preservation and bulk transport of food, as well as improved agricultural methods such as fertilizers, provides improved yields and a much larger area of supply for any given population, making the existence of a crisis a matter of economics and aid.
Malthusianism is a theory in demography regarding population growth. It holds that population expands faster than food supplies. Famine will result unless steps are taken to reduce population growth.
Over the centuries many theorists have considered one or another aspect of population, usually to promote the policy of more people (“pronatalist.”) The early Christian tradition, however, was “antinatalist”, with the highest prestige going to priests, monks and nuns who were celibate.
In the 17th and 18th century the general belief, called "mercantilism" was that the larger the population the better for the nation. Larger population meant more farmers and more food, more people in church (and more prayers), and larger, more powerful armies for deterrence, defense and expansion. People equaled power. As Frederick the Great of Prussia put it, "The number of the people makes the wealth of states." The policy implications were clear: the state should help raise population through annexation of territory and pronatalist subsidies that encourage large families. After 1800, a rising spirit of nationalism called out for more people to make a bigger and more powerful nation.
English writer Reverend Thomas Malthus (1766-1834), in the first edition (1798) of his pamphlet, "An Essay on the Principle of Population" turned the received wisdom upside down. His stunning conclusion was that more people might make it worse for everyone--that overpopulation was bad and unless proper steps were taken, disaster was inevitable. Population growth was exceedingly dangerous, he warned, for it threatened overpopulation and soon we would all starve to death. The British were taking over India at this time, and could see first-hand the horrors associated with overpopulation.
Malthus’s writings had impact because he had a model of society simple enough for any well-educated person to understand. Food depends on the acreage of farm land. Through geographical expansion and more careful cultivation, the amount of farmland can be expanded. The law of diminishing returns states that additional effort is less and less successful--that is, you get your biggest gains at first then after that the gains get smaller and smaller. Because of the law of diminishing returns food production can only grow arithmetically: 1, 2, 3, 4, 5, etc. On the other hand, the population next year depends on the population this year, so it always expands exponentially: 2, 4, 8, 16, 32, 64, etc. In other words, population expands faster than the food supply, and eventually people will starve. The first sign of overpopulation is an excess number of workers accompanied by falling wages and more poverty. Sooner or later the ratio of people to land will cause poverty to turn to starvation; periodic famines occur inevitably and slash the population to acceptable levels before it starts growing again.
Malthus saw two ways to keep population down, "positive" and "preventive" checks. Positive checks were nasty: famine, plague and warfare. Preventive checks included voluntary actions reasonable people could take. Malthus (a clergyman) identified two types of voluntary action, the moral one of deferring marriage, and a variety of "vices" or immoral steps that included birth control, abortion, infanticide, adultery, prostitution and homosexuality.
The Malthus model was unusually powerful: it immediately generated predictions about the fate of mankind. Demography suddenly moved from an abstraction to concrete reality and attracted the attention of scholars and politicians. Economists used the model to show that the more workers there are the lower there wages will be. Charles Darwin made the struggle for food into the centerpiece of his theory of evolution of species. Malthus was a political conservative; one of his goals was to prove that the utopian dreamers of the era of the French Revolution were too optimistic about the future. Malthus's conservative policy prescriptions set the terms of the debate for the entire 19th century. One immediate policy implication was that it was a bad idea for the government to give away food to the poor because poor people would respond by having more children and thus create even more misery. (What England in fact did was set up a relief system under the "Poor Law" that made it very unattractive to live on charity.)
According to Malthus, the cause of poverty was an excess number of mouths to feed, and the fault was with the lack of foresight by the parents. Malthus acknowledged that the unequal distribution of wealth did contribute to poverty but believed that redistributing wealth would only make poverty worse. Strong themes indeed--and ones that echoed in 1996 as the United States Congress sharply cut back on how long poor people could stay on welfare. On an optimistic note, Malthus emphasized that prudence and education could lead to an ever-increasing standard of living for the working class, a proposition that was widely accepted by the 1990s.
Two key assumptions Malthus made were that the lure of sex was so strong that people would have babies no matter what the consequences and that technology would grow slowly or not at all. Both assumptions were wrong. Agricultural productivity has increased faster than population growth, and 200 years after Malthus the per capita food consumption in (nearly) all the world is much higher than it was then. [The exception in recent decades has been sub-Sahara Africa, where Malthusian predictions of overpopulation and famine have come true.] Controversy also surrounds a third argument by Malthus, that only moral restraint should be used to control fertility, and not contraception. (This particular debate continues to rage among Roman Catholics, pitting the Pope who condemns contraception against the laity who insist on practicing it.)
Regarding Malthus’s first assumption, all societies have created mechanisms to control fertility (for example, by delaying marriage until the couple had enough land to feed themselves.) Malthus himself finally recognized this in his second edition of 1803. Everywhere family formation is a social and economic arrangement (not a sexual tryst) and is closely correlated with the supply of land, and jobs. Even before Malthus observers had noted that people delayed marriage if they thought their social status would decline. In the 1803 edition Malthus admitted the existence of what he called "preventive checks," especially the characteristic late marriage pattern of western Europe, which he called "moral restraint." The demographic historian John Hajnal has explored in detail the propensity in Europe in the 18th and 19th century to use delay of marriage as a population control device, tied to the shortage of farmland. (In America, with no shortage of good land, the age of marriage plunged to 18 for women and 20 for men by 1800).
There are two schools of thought that follow Malthus. The "Malthusians" and "Neo-Malthusians." Both see overpopulation as a serious threat to mankind, and both agree about the linkage between unrestrained fertility and poverty. The main difference is that the Neo-Malthusians favor birth control as the main solution and the Malthusians want delayed marriage.
19th century responses to Malthus
Reaction was negative among Christians who felt Malthus denied God's providence and preferred sin and fornication to the misery and degradation of families forced to live in poverty. Later writers discussing marriage, abstinence, contraception, and morality, came to caricature Malthus's original ideas, even in his defense.
Biologist Charles Darwin was strongly influenced by Malthus, and in The Origin of Species (1859) emphasized the "struggle for existence" as a condition that he assumed was universally understood and whose implications were generally accepted.
John Stuart Mill (1806-73), an English economist, argued 150 years ago that the standard of living was the key to desired family size. Mill was a pioneer feminist, and believed that wives wanted fewer children than husbands did, so as women became more liberated the birth rate would fall.
Arsene Dumont, writing 100 years ago in France, stressed the desire of parents to move upward on the social scale, and to gain more wealth. Having fewer children, he argued, saved money and made a rise more possible since the money save could be used for things. Dumont explained the declining French birth rate a century ago in terms of this quest for upward status.
Emile Durkheim, the French intellectual who helped found the discipline of sociology 100 years ago, emphasized the importance of division of labor. He argued there was a threshold "dynamic density" of population. Above a certain density it became easier to divide roles more efficiently as workers became increasing specialized and to improve their lot. This theme was picked up by Ester Boserup in the 1980s.
In Italy the influence of Malthus came after his works were translated in 1868. Filippo Virgilii, an economist and demographer, supported Malthusian ideas; Tullio Martello, a classical economist was one of the few who opposed Malthusianism. In Germany socialist intellectual Karl Kautsky denounced Malthusianism as reactionary, but that there could be a socialist neo-Malthusianism; Kautsky said that only after and because of radical socialist reform could population control be possible.
American statistican Francis Amasa Walker (1840-1897) in the 1890s examined American fertility decline. He combined Malthusianism, Darwinism, and racism to produce a new biological Malthusianism that identified a population calamity more harmful than overpopulation - biological deterioration due to immigration. Other American social scientists widely accepted biological Malthusianism, which helped animate the movement for immigration restriction 1900-1925. 
Robert Owen, and the British proto-socialists, disagrees sharply with Malthus. Karl Marx, the founder of modern socialism, argued that population depends, like everything else, on the ownership of the means of production. This implied there can be no independent laws of population, hence Malthus must be dead wrong. Since poverty could never be the fault of the workers, it had to be blamed on capitalism. Furthermore, if workers reduced their numbers (by having fewer children), they would be politically weakened. Marxism believed that class conflict would eventually cause the overthrow of capitalism. Socialism will ensue, they promised, and cure all evils.
After the 1840s the Marxists tried to counter the influence of the Malthusians. Marx set the tone by vehemently ridiculing Malthus as guilty of spreading a "vile and infamous doctrine, this repulsive blasphemy against man and nature." Marx said that overpopulation can only occur under capitalism, because the capitalists want a large surplus population of workers (the unemployed constituted a "reserve army of labor”) in order to keep wages low and profits high. Under socialism, Marx argued, there would be a perfect harmony of interests, and a population of any size could be supported. The reason was because the surplus product of labor, previously stolen by the capitalists, would be returned to its rightful owners, the workers, thereby eliminating the cause of poverty. (This was the sort of utopianism that Malthus was trying to undercut.)
Malthus and Marx shared a strong concern about the plight of the poor. For Malthus the solution was conservative; he called for individual responsibility--the delay of marriage and childbearing. For Marx the only solution was a revolution that would destroy capitalism and install socialism.
Birth control and neo-malthusianism
Micklewright (1961) surveys the neo-Malthusian phase of the British birth control movement from Francis Place's ideas, c. 1820, to Bradlaugh's death in 1891. The Utilitarians, seeing social utility as the guide in ethics and large families as a cause of poverty, proposed restraint, late marriage, or artificial regulation as a solution. This body of thought came to be known as "neo-Malthusianism." Francis Place had reached this view by about 1820, and although he was unable to get it across to working-class audiences, early converts were Robert Dale Owen and John Stuart Mill, who was arraigned before a magistrate for his views. Numerous pamphlets were circulated in Radical circles in the 1820's and 1830's, and an English edition of the Fruits of Philosophy of Dr. Knowlton of Massachusetts was published. The author suggests that the early Victorian period did not see a slackening of these ideas. In 1854 the secularist Dr. George Drysdale published his Physical, Sexual and Natural Religion, and the defeat of Viscount Amerley in the South Devon election in 1868 for holding neo-Malthusian views, led to the founding of the London Dialectical Society, which illustrated the progress of these ideas among the educated middle class. The Bradlaugh-Besant trial of 1877, which is analyzed, gave immense popular attention for the whole subject. A further cause celèbre was Dr. H. S. Allbutt's removal from the medical register in 1887 for publishing The Wife's Handbook and advertising contraceptives. The decline in neo-Malthusian thought is accounted for by the higher living standards of the late 19th century, and the fact that birth control was now advocated by feminists, advocates of equality of the sexes, or for health reasons.
In the Netherlands the "New Malthusian League" was active from 1881 to 1940. It advocated birth control through the use of contraceptive devices. The league was the creation of Liberal Party politics and the medical profession, and was opposed by both Catholic and Calvinist groups.
Eugenists emerged around 1900 to argue that the human breeding stock could be improved by emphasized selective marriage and large families among the "best" stock -- an argument promoted by Theodore Roosevelt. The best people ignored it. Much more controversial was the recommendation that pooor people ("poor stock") whould limit their birth rates, and that medicine and government should help by making contraception more available. Neo-Malthusians stressed the danger of all population growth regardless of good or bad stocks, and favored birth control for everyone. The two groups were in some respects allies against indiscriminate breeding but in Europe that alliance was shattered, however, by fears of greatly reduced population levels resulting from the deaths and (especially) the low birth rates during World War I.
Kingsley Davis, a leading American demographer of the post-World War II era, brought together the insights of Mill and Dumont. David observed that as infant mortality rates fall more children survive and are expensive to maintain. To keep up living standards, therefore, families have to limit their fertility. Demographer John Caldwell has emphasized the flip side of this argument: children are an economic burden and that is why parents have smaller families.
In the late 20th century Ester Boserup, a Danish demographer, and Julian Simon, an American economist, turned Malthus upside down. They contended that population growth is not necessarily bad and, in fact, may well be beneficial. Boserup reported that in poor agricultural countries population growth led to technical improvements in agriculture, raising productivity and providing more food per person than before. Simon argues that a growing human population is "the ultimate resource." Simon rejects the Malthusian conclusion that poverty is the inevitable result of population growth. Instead he argues that if a society has a certain level of freedom (especially free markets), then more people means more talents and more ideas. In a free market these new talents can be utilized. Productivity will go up for the society as a whole, and everyone will benefit.
The Simon and Boserup argument is not the same as the old nationalist argument (which is still around in some countries) to the effect that having more people means more power. Or more exactly, it is wise to have a larger population than your enemies, and if they are growing faster than you, you are at risk.
Neo-malthusianism and Environmentalism
The environmental movement suddenly sprang into public consciousness about 1970. Some began distrusting technology as an automatic solution, with nuclear energy a special villain. The question was whether modernization and industrialization had already done great damage to the environment. Were there too many people for the earth to support? Major famines struck India (mid-1960s), Ethiopia (1971-73) and Bangladesh (1974), and repeatedly in sub-Saharan Africa (mid-1980s). These disasters led to serious warnings that indicted overpopulation, food shortages, and limits of growth as the causes. New groups such as Lester Brown's Worldwatch Institute and the Club of Rome highlighted the danger of world hunger.
The environmental alarm ringers incorporated a Neo-Malthusian model into their theses. Garrett Hardin epitomizes Neo-Malthusianism in the context of environmentalism in “The Tragedy of the Commons,” (1968). His famous parable of the 'tragedy' compares the human decision of having a child to that of a herdsman deciding whether to place another head of livestock onto a town common. As each herdsman in turn acts in self-interest, the commons becomes overburdened to the point of complete destruction. Hardin echoed Malthus in arguing that the world has limits to food productivity and humans have the reproductive capacity to stretch those limits past the brink. He concluded, "A finite world can support only a finite population; therefore, population growth must eventually equal zero."
Paul Ehrlich in 1970 warned the "death of the world is imminent":
- Because the human population of the planet is about five times too large, and we're managing to support all these people--at today's level of misery--only by spending our capital, burning our fossil fuels and turning out fresh water into salt water. We have not only overpopulated but overstretched our environment. We are poisoning the ecological systems of the earth....
As the environmental movement grew strength after 1970, Ehrlich's warnings were taken to heart by many activists. Although the world did not come to an end, neither did Ehrlich's warnings, despite attacks on his position by Julian Simon. In The Population Explosion (1991) he and Anne Ehrlich vividly warned how the Earth's population, growing by 95 million people a year, is rapidly depleting the planet's resources, resulting in famine, global warming, acid rain, and other major problems. The Ehrlich's main thrust was not so much human misery as ecological misery: overpopulation is rapidly injuring or destroying the environment, and besides the long-term harm to humans, that damage is itself utterly wrong. By the 21st century environmentalist concern had switched from overpopulation to global warming.
Spengler (1979) shows that since their defeat by Germany in 1870 the French have been highly concerned with virility and remaining a great power. Behind this concern was an early and unprecedented decline in fertility. Pronatalist concern came from varied social, economic, and political sources. In time, national policies favoring large families were passed, the Vichy regime being especially active. These measures masked a steady Malthusianist undercurrent, and although the population advanced from the 1940's through the 1960's, once again a population crisis exists.
Uses by historians
Neo-Malthusian historians M. M. Postan and Emmanuel Le Roy Ladurie explained the decline of feudalism in terms of impersonal economic and demographic forces. To the contrary, argued Marxist Robert Brenner, who stressed instead the role of class struggle between lords and peasants in medieval Europe.
- Ester Boserup. Population and Technological Change: A Study of Long-Term Trends (1981) (1981),
- Ansley J. Coale and Susan C. Watkins, eds. The Decline of Fertility in Europe, (1986)
- Davis, Kingsley. "The World Demographic Transition." Annals of the American Academy of Political and Social Science, 1945237: 1-11. in JSTOR, classic article that introduced concept of transition
- Dolan, Brian, ed. Malthus, Medicine and Morality: "Malthusianism" after 1798. 2000. 232 pp.
- Gillis, John R.; Louise A. Tilly; and David Levine; eds. The European Experience of Declining Fertility, 1850-1970: The Quiet Revolution. 1992.
- Susan Greenhalgh. "The Social Construction of Population Science: An Intellectual, Institutional, and Political History of Twentieth-Century Demography," Comparative Studies in Society and History, Volume 38, Issue 1 (Jan., 1996), 26-66. in JSTOR
- Hauser, Philip M., and Otis Dudley Duncan, eds. The Study of Population: An Inventory and Appraisal. 1959. sumamry of field at mid-century
- Malthus, Thomas. An Essay on the Principle of Population (1st ed 1798) (Cambridge Texts in the History of Political Thought) ed by Donald Winch 1992 ISBN 9780521429726
- Micklewright, F. H. A. "The Rise and Fall of English Neo-malthusianism." Population Studies 1961 15(1): 32-51.
- Reed, James. From Private Vice to Public Virtue: The Birth Control Movement and American Society Since 1830. 1978.
- Spengler, Joseph J. France Faces Depopulation (2nd ed 1979)
- John R. Weeks. Population: An Introduction to Concepts and Issues (10th ed. 2007)
- Dennis Hodgson, "Ideological Currents and the Interpretation of Demographic Trends: the Case of Francis Amasa Walker." Journal of the History of the Behavioral Sciences 1992 28(1): 28-44. Issn: 0022-5061 fulltext in Ebsco
- Samuel Hollander, "Marx and Malthusianism: Marx's Secular Path of Wages." American Economic Review 1984 74(1): 139-151. Issn: 0002-8282 Fulltext: in Jstor and Ebsco
- Julian L. Simon, "The Effects of Population on Nutrition and Economic Well-being." Journal of Interdisciplinary History 1983 14(2): 413-437. Issn: 0022-1953 Fulltext: in Jstor; Dennis A. Ahlburg, "Julian Simon and the Population Growth Debate" Population and Development Review Vol. 24, No. 2 (Jun., 1998), pp. 317-327 online in JSTOR
- T. H. Ashton and C. H. E. Philpin, eds. The Brenner Debate: Agrarian Class Structure and Economic Development in Pre-Industrial Europe (1985)