In this article, You will read the Optimum Population Theory – for UPSC (Population and Settlement Geography – Geography Optional).

Optimum Population Theory

The optimum population is the ideal population which combined with other available resources or means of production of the country will yield the maximum return or income per head.

The concept of the optimum population was first propounded by Confucius.

  • ‘Excessive growth may reduce output per worker, repress levels of living for the masses and engender strife’. -  Confucius (551 – 479 BCE)

In the 19th century, the first beginnings of this concept may be traced to the writings of a German professor, Karl Winkelblech (1810-1865), who while describing population theory and policy, classified nations into three categories according to the size of their population:

  1. Under-populated nations
  2. Over-populated nations; and 
  3. Nations with normal populations, meaning a size favourable to the greatest possible productivity.

The optimum theory of population was propounded by Edwin Cannan in his book Wealth(1924).

The theory was popularised by Robbins, Carr Saunder, and Dalton.

  • Robbins defines it as ‘the population which just makes the maximum returns possible is the optimum population or the best possible population’.
  • Carr-Saunders defines it as ‘that population which produces maximum economic welfare.’
  • According to Dalton, ‘Optimum population is that which gives the maximum income per head.’
  • Dalton’s view is more scientific and realistic.
Optimum Population Theory - UPSC


Optimum Population Theory is based on the following assumptions:

  1. The natural resources of a country are given at a point of time, but they change over time.
  2. There is no change in techniques of production.
  3. The stock of capital remains constant.
  4. The habits and taste of the people do not change.
  5. The ratio of the working population to total population remains constant even with the growth of population.
  6. Working hours of labour do not change.
  7. Modes of business organisation are constant.

The Theory

  • The optimum population is that ideal size of population which provides the maximum income per head.
  • Any rise or reduction in size of population above or below the optimum level will diminish income per head.
  • Given the stock of natural resources, the technique of production and stock of capital in a country, there is a definite size of population corresponding to highest per capita income.
  • Other things being equal, any deviation from optimum size population will lead to reduction in per capita income.
  • If the increase in population is followed by the increase in per capita income, the country is under-populated and it can afford to increase in population till it reach the optimum level.
  • If the increase in population leads to diminution of per capita income, the country is over-populated and needs a decline in population till the per capita income is maximised.
  • The per capita income is the highest at the optimum point, after that the average product of labour start falling.
  • Optimum population is not fixed point, it changes with the change in any of the factors.
  • If there is improvements in methods and techniques of production, the output per head will rise and the optimum point will shift upwards.
  • With increase in stock of natural resources, the optimum point of the country will increase.
Optimum Population theory of population
Dalton’s Formula
  • Dalton has deduced overpopulation and under population which result into deviation from optimum level of population in the form of a formula.
  • The deviation from the optimum is maladjustment(M).
  • Maladjustment is a function of two variables, the optimum level of population O, and the actual level of population A.
  • Then the maladjustment is M= ((A – O) / O
  • If M is positive, the country is overpopulated, and if it is negative, the country is under populated.
  • When M is 0, the country possesses optimum population.
P Sengupta’s formula
  • I = (P1-P)/A
  • Where I is the index of population
  • P1 is the rural population capable of being supported by land resource base.
  • P is the actual rural population.
  • A is the total area.
  • This method has applicability in India which is an agrarian country.

Some examples of optimum population

  • USA is not overpopulated despite being the third largest in terms of population but Saharan countries are overpopulated due to lack of utilization of resources.
  • The population density of Singapore is high but it has been able to sustain its population effectively due to efficient utilization of resources.

Superiority over Malthusian Theory

  • The theory is superior to Malthusian theory as it is applicable to all countries irrespective of their economic conditions.
  • The theory related the problem of the population to the total population of the country, both agricultural and industrial.
  • The concept is dynamic as over the period of time, per capita income may increase with the expansion of the output due to improvement in knowledge, skill, capital, equipment.
  • The theory adopts an optimistic and realistic viewpoint towards the problem of population.

Critical Analysis

Despite the superiority of the optimum theory over the Malthusian theory of population, it has serious weaknesses.

  • No Evidence of optimum level in any country
  • Difficult to measure optimum level
  • Correct measure of per capita income is not possible
  • Neglects the distribution aspects of per capita income
  • Optimum level not fixed but changes with time
  • Neglects social and institutional conditions
  • No place in state policies
  • Does not explain the determinants of population growth.

  • If the population is above the optimum, the negative effects of overcrowding (pollution, crime, social dysfunction, etc.) and environmental damage reduces welfare or there are too few resources to maintain the population as its current level. The law of diminishing returns begins to operate. Up to a certain limit, the increase in population is matched by an increase in output and production, but after a certain point, the output per capita falls, which results in more people becoming dependent on same resource base and thus each individual will become poorer. Further, there may be out-migration from such region. The concept of overpopulation has been divided by Clarkas follows:
    • Absolute overpopulation-It refers to the prevalence of low standard of living even after maximum resource development.
    • Relative overpopulation: In this, the present production of an economy is inadequate, but can increase with technological advancement.
Under population
  • Contrary to the above, there are not enough people to develop all the resources of an area, its standard of living may remain lower than it could be, where its full potential is realized. If the population is below its optimum, it can increase with a net social benefit without damaging the natural resources needed for the population. E.g. Central Asia.
Optimum population
Important determinants of population:
  • Demographic structure like mortality which may create a situation of under population.
  • Available resource and Technology: The concept of the optimum population assumes that the techniques of production, the stock of capital and natural resources, the habits and tastes of the people, the ratio of working population to total population, and the modes of business organisation are constant. But all these factors are constantly changing. As a result, what may be the optimum at a point of time might become less or more than the optimum over a period of time.
Available resource and technology
  • Per capita production, average standard of living and rational utilisation of resources also determines the population of a region.
Per capita production and Population
  • In the figure given below, AP1is the average product of labour or per capita income curve. Suppose there is an innovation which brings a change in the techniques of production. It shifts the per capita income curve to AP2. As a result, the optimum level of population rises from OP1 to OP2 with the increase in per capita income E from P1M1 to P2M2. If the per capita income rises further due to a change in any of the above assumed factors, the AP2, curve will shift upward.
size of population graph

Methods to tackle Overpopulation and Underpopulation

  • Methods to tackle over and under population include migration and technology transferetc.
  • Migration from the regions of overpopulation such as South Asia to under-populated ones like Middle East might lead to economicbenefits for both the regions.
  • Similarly diffusion of technology between developed and developing countries may also enable the latter to enhance their technology level thereby allowing for more efficient resource utilization.

The population is converted to overpopulation when:

  • When number of people in an area exceeds the carrying capacity of land.
  • Number of natural resources is not sufficient to fulfil the needs of existing population.
  • The rate of growth of population is greater than the rate of growth of development.
  • Per capita income in the region is too less to maintain the basic need.
  • Overpopulation also leads to over exploitation of resources which affects the sustainable growth of a region.

Ackerman’s Classification

Ackerman’s system of population resources regions adopted here must not be regarded as the ultimate tool in analyzing population-resource nexus but only as a promising beginning. “Ackerman used three basic criteria for devising the world’s regional scheme of population-resource ratio. These include:

  • Population factor
  • Resource factor
  • Technology factor

The most critical is the magnitude and quality of available technology, Gersmehl(2005)”. Where the technology is highly developed and the technically skilled personal are abundant, as in the US and Europe, the resources and prosperity are at adequate thought not necessarily at optimum level. “Ackerman while using the three factors of population, resource and technology put greater emphasis upon the technology, ibid (2005)”.

Therefore, Ackerman classified the world into five population resource regions

  • United States Type or Technology-Source Area of Low Population-Potential/Resource Ratio:
    • These areas are the most developed areas of the worldenjoying very high standard of living.
    • They witness rapid development in last oneto two hundred years as they received massive in-migration from then technically very advance society. In fact at that time most of them belong to Brazilian type.
    • These lands were full of pristine natural resources and thus technological support gave themvery high growth and prosperity.
    • Slowly they mastered in technologyand now the area has so much technology and so many technical persons that they often export them.
    • Examples are: United States of America, Canada, Australia, New Zealand, Argentina and parts of Russia, etc.
  • European Type or Technology-Source Area of high Population-Potential/Resource Ratio
    • This is the source area of massive out-migration to new lands which developed into United States type latter.
    • Here again technology is very advance but high population and limited physical resources has created high population pressure.
    • High living standard is maintained by constant technological up-gradation, resource conservation and recycling, one of the best output practices along with export of technology, technical knowhow and export of finished goods.
    • Examples are: The most of countries of Western, Southern and Eastern Europe and Soviet Central Asian republicsbelongs to this group.
  • Brazilian Type or Technology-Deficient Area of low Population-Potential/Resource Ratio
    • This is practically a transition stagewere the pressure of population to physical resources is low and so these areas have high promises.
    • They have ample physical resources but their technologies are poorand so their prosperity is average.
    • If they receive or develop good technology, sufficient social overhead capital, etc. then their resource exploitation efficiency will expand and it will bring them to a trajectory of higher prosperity like of European type.
    • Examples are: Cover most Brazilian plateau, Bolivia, Venezuela, Paraguay, interior Argentina, Central American Republics, Cuba, north Australian territory, etc
  • China or Egyptian Type or Technology-Deficient Area of high Population-Potential/Resource Ratio
    • This is the least promisingof all categories.
    • State of technology is poor and excessive populationhas caused very high stress on physical resources.
    • So, industrialisation is low, agriculture which is the mainstay of economy is in dilapidated condition and high population is expanding at higher rate.
    • Many social evils like poverty, unemployment, malnutrition, illiteracy, etc. are very common.
    • Examples are: Egypt, Algeria, Tunisia, Morocco, Albania, Greece, Haiti, Guatemala, China, India, Pakistan, Sri Lanka, Afghanistan, etc.
  • Arctic-Desert Type or Technology-Deficient Area with few Food Producing Resources
    • This is the land of the future with many unexplored resourcesdue to the lack of technological maturity.
    • Either uninhabited or a very few peoplereside there
    • So technological advancement may invite more human intervention in these areas of hostile geo-environmental conditions in future.
    • Examples are: Covers the Antarctica, northern part of North America and Eurasia, the Amazon basin, the Sahara desert, desertsof Central Australia, Chile, Patagonia, etc.
Ackerman’s Classification

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