Malthusian crisis

 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.

This concept was proposed by the Reverend Thomas Malthus in 1798 in his "Essay on the Principle of Population". Malthus was an English economist.
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.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.