Malthusian Theory of Population

The Malthusian Theory

Amongst the well-known theories of population, the Malthusian theory is one of the oldest. Thomas Robert Malthus, an economist explained this theory in his 1798 essay on the ‘Principle of population’. He then modified some parts in the essays next edition in 1803. 


To Quote His Own Words:

“By nature, human food increases in a slow arithmetical ratio; man himself increases in a quick geometrical ratio unless want and vice stop him. The increase in numbers is necessarily limited by the means of subsistence Population invariably increases when the means of subsistence increase, unless prevented by powerful and obvious checks.”        

This can be simplified as the following; the human population grows in an exponential format, it increases according to birth rate and with respect to that the food supply increases at a slower rate. If the population keeps on increasing there will be a limit and shortage of food. The shortage of food also indicates the increasing population. This increasing growth if not checked can put a strain on the economy, the environment, government, and the overall infrastructure of various social institutions. 


A simple example can be that in a family if every member of the family reproduces, the family tree will continue to grow, but food production grows at an arithmetic rate which means that it only increases at certain points of time. If left unchecked, as per the theory, a population would outgrow its resources.

Critical Elements of The Malthusian Theory of Population Growth

There are four major or critical elements of Malthusian theory. These are explained below.


Population and Food Supply: Malthus theorised that any population grows in geometric progression. It’s a sequence of numbers where each term after the first is the result of multiplying the previous term with a fixed non-zero number. This non-zero number is called the common ratio. 


An example can be the following sequence: 5,10, 50, 250, 1250….the common ratio is 5


Coming to food resources, the production increases in an arithmetic progression which is a sequence of numbers in such a manner that the difference between back-to-back terms is a constant.


Example: 3, 7, 11,15,19… the common difference is 4.


From this, he derived that a population grows faster than the supply of food and exponential growth in population will lead to a shortage of food.


Preventive Checks: The principle behind this check is to bring down the birth rate to control the population. Preventative checks arise from fore-sight which enables anyone to see distant consequences if he has a large family. If the family has many children the standard of living is bound to be low. The only way anyone can support a large family would be through strenuous labour than what he does in the present state. If he is not able to support the family then the family members may be exposed to poverty. So, man must self-restraint himself from marriage or starting a family unless he thinks that he can support a family. 


Positive Checks: The basis of this check is that population growth is shortened by various factors such as warfare, disease, famine, etc. As a result of these factors, the population would be reduced to a level that can be sustained by the available quantity of food supply. Malthus stated that positive checks would result in a Malthusian catastrophe which forces a return of a population to basic survival.

Why Was The Malthusian Theory of Population Criticised?

Since its inception, the Malthusian theory attracted criticism because of its principles. Below is a summary of some of the grounds on which the theory has been criticised.

Malthus made gloomy forecasts about the economic conditions for future generation based on population growth. However, contrary to the theory, the human population has not increased rapidly and the production of food has increased due to the technological advancement in the agricultural and other food sectors. The living standards of the human population has improved.

  • One of the major supporting factors behind Malthus’s theory was that food production would not be able to keep pace with population growth due to the operation of diminishing returns in agriculture. However, recent advancements in technology along with large capital investments in the agricultural sector has been able to postpone the stage of diminishing returns. Usage of high-quality seeds, fertilisers pesticides and top-grade machinery have assisted agricultural growth. One of the best examples regarding the aspect is the Green Revolution in India. Introducing improved methods in farming and new inventions have increased food production to such an extent that it can sustain a growing population.

  • Malthus stated that fertile lands used for food production were available in limited quantities, that is why food production can never rise faster than population. However, he never took account of different types of food production whilst considering the size of the population.

  • England did face a shortage of agricultural land and if the country had to feed its population through farming then it would have suffered from famines. However, that was not the case as the industrial revolution made use of the country’s various natural resources such as coal and iron and made goods which were exported to other countries in exchange for food. Malthus made the mistake of only considering agriculture and food production when it came to sustaining a growing population.

  • Malthus did not provide calculations for arithmetic growth of food and geometric growth of population. Present-day experts have pointed out that the growth rates in both matters are inconsistent with respect to Malthus’s predictions.

The Importance of The Malthusian Theory:

There are some elements of the Malthusian theory which have some weightage. Humans have a strong desire to reproduce. This is to maintain the family lineage and legacy. So the population is bound to grow rapidly if birth control measures are not taken.


Malthus’s assumptions regarding positive checks are true to a certain extent. History has shown that whenever there is an increase in population for any country, thousands have died due to natural calamities.


After studying these points, one can say that the theory is valid to a certain extent. Some of the leading economists of modern times have observed that Thomas Malthus in this theory regarding population growth have stated the partial truth and no one can deny that.


Malthusian Theory Summary

Based on the principles of the Malthusian theory it can be summarised into the following points:

  • The growth of the human population is much faster than the rate of growth for the means of subsistence such as food, clothing, and other agro-products.

  • As the production rate of agro products is slower it is surpassed by population growth which results in the onset of poverty

  • Control of growth of population is important to sustain the population.

  • Positive checks restore the balance between the increased growth rate of population and food supply.


FAQ (Frequently Asked Questions)

1. Is the Malthusian theory of population applicable today?

Despite the criticism that the theory has faced since it was introduced, the theory does apply to overpopulated countries. One such example is India because of the following reasons

  • India’s population rate is growing at a rate of 2.3% per annum

  • In-spite of the Green Revolution India still imports millions of tons of food grains because of food shortage due to population growth.

  • 39% of the population in India lives below the poverty line. 

  • The life expectancy of an Indian is 60 years which is comparatively lower than other countries

  • The death rate is 11 per 1000 and it shows that natural calamities such as floods, diseases, and hunger are not under full control.

Not only India, in underdeveloped countries of Africa the population is growing at a faster rate than the supply rate of food resulting in deaths by starvation. Thus the Malthusian theory applies to countries' growth of population rate is more, food production is less and natural calamities are not kept in check.


2. What is the Malthusian Trap?

The Malthusian Trap, which is also known as the “Malthusian Population Trap” is the idea that increased levels of food production created by modern agricultural techniques are one of the reasons behind higher population levels. This in-turn again leads to food shortages because of the high demand of grains needed for the growing population 

According to Malthus, even as the evolution in technology would generally lead to per capita income gains, these gains are not achieved because through the practice of utilising modern technology, it also creates population growth. Once the population exceeds what food supplies can support, it would result in a Malthusian crisis such as famine or disease which would increase the death rate and reduce the size of a population.