Prof. Prabha Panth
“Essay on the Principle of Population”
Unlike Smith, he looked not at wealth, but
Economic growth is not automatic,
It is not smooth, but has fluctuations,
Population growth will overtake growth of
food, leading to increasing poverty.
Three classes – workers, landlords and
Total supply of land is fixed,
Diminishing returns on land,
Growth of population is directly related to
the wage rate (w).
As w increases, population increases,
and if w decreases, population decreases.
Workers and landlords only consume
Increase in investment, leads to increase
Increase in capital increases output and
Per capita income also increases.
But Malthus felt this will not continue
Population growth is a function of wage
When wage rate increases, birth rate also
increases, population increases
When wage rate decreases, death rate
increases, population decreases.
So with more growth, more output, and
This cannot be sustained, due to
Prof. Prabha Panth
Rate of population growth
Population grows geometrically
But food production grows arithmetically
So as economic growth continues, the gap
between food and population will widen,
This will eventually lead to fall in standards
of living, and increasing poverty.
This is known as the “Iron Law of Wages.”
Population and food growth
g=a x 2
y1 10 10
y2 20 12
y3 40 14
y4 80 16
y5 160 18
This is known as the “Malthusian Trap”
When economic growth takes place, it will
not improve the conditions of workers,
Higher growth, leads to increase in wage
Higher wage rates leads to increase in
population. Demand for food rises,
But food does not grow at the same rate
The increasing gap, leads to
poverty, hunger, death, more misery.
Malthus suggests that population growth should
This can be done by „Voluntary‟ or „Positive‟
Such as birth control, late marriages, family
Otherwise, there will be „Negative‟ checks to
population growth –
Famines, floods, wars, diseases will increase
death rate, and bring population down to
Pessimistic view of the economy
Data of developed countries shows that as
PCY increased, birth rates automatically
Called “demographic transition”
Output of food has also increased, due to
Imports and free trade of food can take
place, Malthus was for Protection.
Malthusian theory is still applicable to less
Increasing population is consuming all the
surplus, nothing available for investment.
Inferior land is used, and output falls,
Technology is inferior,
In recent times, the depletion of natural
resources, has shown the importance of
Malthusian theory of exponential growth in a