Malthusian theory of population

Also called: Malthusianism · Topic: World Population: Distribution, Density, Growth and Migration · NCERT: Class 12, Ch 2 "The World Population: Distribution, Density and Growth"

Meaning

Malthusian theory of population (also called Malthusianism) is the idea of Thomas Malthus (1798) that population tends to grow faster than the food supply. If nothing checks this growth, it ends in a crash through famine, disease and war.

It is the starting point of the "people versus resources" debate. Every later view is either a revival of Malthus or an answer to him: Neo-Malthusianism, Boserup, Sen, Julian Simon and the demographic transition.

Explanation

Who said it, and why

• Thomas Malthus was an English economist and demographer (a person who studies population).
• His book came out in 1798. Its full title was An Essay on the Principle of Population as It Affects the Future Improvement of Society, with Remarks on the Speculations of Mr. Godwin, M. Condorcet, and Other Writers [3].
• It was a reply to two optimists:
• Godwin and Condorcet believed society could keep getting better [3].

• Malthus argued that population pressure would always pull society back into poverty.

• He believed poverty and misery could not be escaped without strict limits on having children [3].

How the crash happens (cause → process → result)

• Cause: two different rates of growth
• Population grows geometrically, so it keeps doubling: 1 → 2 → 4 → 8 → 16.

• Food grows arithmetically, so it rises by the same amount each time: 1 → 2 → 3 → 4 → 5.

• Process: the gap widens

• Each generation, food per person falls.

Generation	Population (geometric)	Food (arithmetic)	Food per person
1	1	1	1.0
2	2	2	1.0
3	4	3	0.75
4	8	4	0.5
5	16	5	~0.31

• Result: the crash
• In the end, famine, disease and war cut the population back down to what the food can support.

The two kinds of checks

• A check is anything that slows or stops population growth.

Feature	Preventive checks	Positive checks
What they act on	Birth rate (they lower it)	Death rate (they raise it)
Examples	Late marriage, moral restraint (choosing not to have children), celibacy (staying unmarried)	Famine, disease, war
Who controls them	Human choice	Nature or disaster
Malthus's view	Better	Painful, to be avoided

• Malthus said preventive checks are better than positive checks.
• His view grew milder over time:
• His first essay was very gloomy.

• By the time he wrote for the 1824 Supplement to the Encyclopædia Britannica, he gave more space to the milder preventive checks, such as delaying marriage and childbearing on purpose [3].

• NCERT's position: NCERT presents Malthus under "Population Control Measures". It says that for resources to stay sustainable, the world must control a rapid rise in population.

Why the forecast failed: the main critiques

• Technology raised food output faster than "1, 2, 3, 4"
• The agricultural revolution, and later the Green Revolution (high-yielding seeds, irrigation and chemical fertilisers from the mid-1960s), raised food output far faster than he expected.

• India's foodgrain output was 251.54 million tonnes in 2015-16, 332.30 million tonnes in 2023-24 and a record 357.73 million tonnes in 2024-25 [6].

• Fertility fell on its own as countries developed

• This is the demographic transition: as a society becomes richer, more urban and better educated, it moves from high birth and death rates to low ones.

• Growth slows without famine or war.

• Ester Boserup (1965) turned Malthus around

• For her, food supply is not fixed. It responds to population.

• More people press on the land, so farmers work it harder: they shorten fallow periods and use irrigation, terracing, the plough and manure. Output per hectare rises.

• Amartya Sen: famine is about access, not just numbers

• Entitlement is a person's ability to get food: by growing it, buying it with wages or receiving it from the state.
• Famines often come from entitlement failure, not simply from too many people and too little food.

Where it occurs

• India: the forecast proved wrong in practice
• Food supply kept growing while India's population passed 1.4 billion.
• In 2024-25, rice reached a record 150.18 million tonnes and wheat a record 117.94 million tonnes [6].
• Total Fertility Rate (TFR) is the average number of children a woman would have in her lifetime. India's TFR fell from 2.2 (NFHS-4, 2015-16) to 2.0 (NFHS-5, 2019-21). This is below the replacement level of 2.1 (the TFR at which each generation just replaces itself) [4].

• TFR stayed at 2.0 in NFHS-6, and 31 of 36 States/UTs have reached replacement-level fertility [5].

• Bengal, 1943: a famine that Malthus does not explain

• Wartime inflation priced food out of reach for rural labourers, fishermen and artisans.

• Millions died even though total food in Bengal had not fallen sharply. This is Sen's case of entitlement failure.

• The world: transition, not crash

• World population reached 8 billion on 15 November 2022. The rise came mainly from longer lives, because deaths fell, not because births rose [2].
• Going from 7 to 8 billion took 12 years. Going from 8 to 9 billion will take about 15 years, to 2037 [2].

• UN projections: about 8.5 billion in 2030, 9.7 billion in 2050, and a peak of about 10.4 billion in the 2080s [2].

• Underpopulation, the opposite of the Malthusian fear: historically Australia and Canada had too few people to use their resources fully.

Don't confuse with

• Neo-Malthusianism: a 20th-century revival of Malthus's fear, seen in The Population Bomb (1968, Paul Ehrlich) and The Limits to Growth (1972, Club of Rome). Malthus preferred moral restraint. Neo-Malthusians openly support birth control (contraception and family planning).
• Boserup's theory (1965): Malthus says population growth outruns food. Boserup says population pressure drives farm innovation, so food rises to match.
• Julian Simon's Cornucopian view (1981): he called human ingenuity (creativity and problem-solving) the "ultimate resource". More people means more minds to solve shortages. This is the exact opposite of Malthusian pessimism.
• Demographic transition: Malthus expected growth to stop through rising deaths (positive checks). The transition shows growth slowing through falling births as societies develop.

Prelims Hooks

• An Essay on the Principle of Population (1798), by Thomas Malthus, was a reply to Godwin and Condorcet [3].
• Population grows geometrically (1, 2, 4, 8). Food grows arithmetically (1, 2, 3, 4).
• Trap: famine, disease and war are positive checks (they raise deaths). Late marriage, moral restraint and celibacy are preventive checks (they lower births). Malthus preferred preventive checks.
• Match the pairs: Boserup (1965), population pressure drives innovation; Sen, entitlement failure (Bengal 1943); Ehrlich, The Population Bomb (1968); Julian Simon, "ultimate resource" (1981).
• India's TFR is 2.0 (NFHS-5), below the replacement level of 2.1 [4]. India's foodgrain output hit a record 357.73 million tonnes in 2024-25 [6].

Mains Points

• Why Malthus was proved wrong in practice (GS-I/III):
• The Green Revolution broke the "arithmetic food" assumption. India's foodgrains rose from 251.54 MT in 2015-16 to 357.73 MT in 2024-25 [6].
• The demographic transition broke the "geometric population" assumption. India's TFR is now 2.0 [4][5].

• Growth was checked by choice (preventive checks), not by disaster (positive checks).

• Famine and food security policy:

• Sen's entitlement approach moves the focus from total food output to access: wages, prices and the public distribution system.

• This supports a rights-based approach to food security, not just production targets.

• What survives of Malthus today:

• The Neo-Malthusian famines predicted for the 1970s–80s did not happen.
• Still, carrying capacity (the largest population an area can support over the long term without damaging it) and planetary limits now shape debates on climate, water and land degradation.
• The key question has shifted from how many people there are to how much each person consumes. The policy answer is investment in human capital, farm technology and resource efficiency, along with voluntary family planning (National Population Policy 2000) [5].

Related concepts

• Preventive and positive checks
• Neo-Malthusianism
• Optimum population

Read more

• Population and resources: Malthus and after