More recently, however, several countries such as China, Japan,[1][2] South Korea,[3] Russia,[4] Iran, Italy,[4] Spain, Finland,[5] Hungary[6] and Estonia[7][8] have begun efforts to boost birth rates once again, generally as a response to looming demographic crises.

Chanakya favored the remarriage of widows (which at the time was forbidden in India), opposed taxes encouraging emigration, and believed in restricting asceticism to the aged.

[11] Confucius (551-478 BC) and other Chinese writers cautioned that, "excessive growth may reduce output per worker, repress levels of living for the masses and engender strife."

[12] Not only did he conclude that overpopulation was the root cause of the intensification of political and social conflict, but he also reduced traditional morality to an evolutionary product of material surplus rather than having any objective value.

[9] He wrote: "The strongest witness is the vast population of the earth to which we are a burden and she scarcely can provide for our needs; as our demands grow greater, our complaints against Nature's inadequacy are heard by all.

The scourges of pestilence, famine, wars, and earthquakes have come to be regarded as a blessing to overcrowded nations since they serve to prune away the luxuriant growth of the human race.

"[13] When Russian explorer Otto von Kotzebue visited the Marshall Islands in Micronesia in 1817, he noted that Marshallese families practiced infanticide after the birth of a third child as a form of population planning due to frequent famines.

"[16] Jean Bodin, a French jurist and political philosopher (1530–1596), argued that larger populations meant more production and more exports, increasing the wealth of a country.

[16] Giovanni Botero, an Italian priest and diplomat (1540–1617), emphasized that, "the greatness of a city rests on the multitude of its inhabitants and their power," but pointed out that a population cannot increase beyond its food supply.

[15] With the onset of the Thirty Years' War (1618–48), characterized by widespread devastation and deaths brought on by hunger and disease in Europe, concerns about depopulation returned.

There is a constant effort towards an increase in population which tends to subject the lower classes of society to distress and to prevent any great permanent amelioration of their condition….

But the disease is so far advanced that only with radical surgery does the patient have a chance to survive.In his concluding chapter, Ehrlich offered a partial solution to the "population problem", "[We need] compulsory birth regulation... [through] the addition of temporary sterilants to water supplies or staple food.

[24] Since Ehrlich introduced his idea of the "population bomb", overpopulation has been blamed for a variety of issues, including increasing poverty, high unemployment rates, environmental degradation, famine and genocide.

[25][26] A letter in response, published in the same journal, argued that a reduction in population by 1 billion people in 2100 could help reduce the risk of catastrophic climate disruption.

[27] A 2021 article published in Sustainability Science said that sensible population policies could advance social justice (such as by abolishing child marriage, expanding family planning services and reforms that improve education for women and girls) and avoid the abusive and coercive population control schemes of the past while at the same time mitigating the human impact on the climate, biodiversity and ecosystems by slowing fertility rates.

[28] Paige Whaley Eager argues that the shift in perception that occurred in the 1960s must be understood in the context of the demographic changes that took place at the time.

He claimed that human beings are the ultimate resource since we possess "productive and inventive minds that help find creative solutions to man’s problems, thus leaving us better off over the long run".

Many prominent personalities, such as Bertrand Russell, Margaret Sanger (1939), John D. Rockefeller, Frederick Osborn (1952), Isaac Asimov, Arne Næss[37] and Jacques Cousteau have also advocated for population planning.

Today, a number of influential people advocate population planning such as these: The head of the UN Millennium Project Jeffrey Sachs is also a strong proponent of decreasing the effects of overpopulation.

[50] Pope Benedict XVI has stated, "The extermination of millions of unborn children, in the name of the fight against poverty, actually constitutes the destruction of the poorest of all human beings.

The Socialist Republic of Romania under Nicolae Ceaușescu severely repressed abortion, (the most common birth control method at the time) in 1966,[53][54] and forced gynecological revisions and penalties for unmarried women and childless couples.

[57] As part of China's planned birth policy, (work) unit supervisors monitored the fertility of married women and may decide whose turn it is to have a baby.

[61] According to Tibetologist Melvyn Goldstein, natalist feelings run high in China's Tibet Autonomous Region, among both ordinary people and government officials.

Where women are well educated they tend to choose to have smaller families… What Kerala shows is that you don't need aggressive policies or government incentives for birthrates to fall.

[75] In Israel, Haredi families with many children receive economic support through generous governmental child allowances, government assistance in housing young religious couples, as well as specific funds by their own community institutions.

[80] Russian President Vladimir Putin directed Parliament in 2006 to adopt a 10-year program to stop the sharp decline in Russia's population, principally by offering financial incentives and subsidies to encourage women to have children.

[81] Singapore has undergone two major phases in its population planning: first to slow and reverse the baby boom in the Post-World War II era; then from the 1980s onwards to encourage couples to have more children as the birth rate had fallen below the replacement-level fertility.

[86] In May 2012, Turkey's Prime Minister Recep Tayyip Erdogan argued that abortion is murder and announced that legislative preparations to severely limit the practice are underway.

[91] In a 2004 editorial in The New York Times, David Brooks expressed the opinion that the relatively high birth rate of the United States in comparison to Europe could be attributed to social groups with "natalist" attitudes.

It is reported that Uzbekistan has been pursuing a policy of forced sterilizations, hysterectomies and IUD insertions since the late 1990s in order to impose population planning.