It is often asserted by those of the Hindutva persuasion that one of the
major threats to "freedom" in India is from the increase in numbers of
the Muslim population. For decades, they have been predicting an imminent
taking over of the Indian polity by Muslims due to this rise. For instance,
they claim that once the Muslim population reaches 25%, another bout of
separatism will occur (as in 1947).
Currently, the claims are based on the following snippet from the Indian
Census of 1991:
Total Indian Population in 1991 = 816 million
Indian Muslim Population in 1991 = 101 million (12.1% of total)
% Increase in Total Population since 1981 = 23.8
% Increase in Muslim Population since 1981 = 32.8
(Source: Census of India 1991, Series-1, Paper 1 of 1995, Religion. These
figures do not take into account the state of Jammu & Kashmir, since the 1991
Census could not be conducted there.)
In this page, we make a few rough, order-of-magnitude calculations
of the numbers involved and their actual consequences. Using t for time,
with origin at 1991,
T for total Indian population and M for the population of Indian
Muslims, the relevant exponential equations are:
T(t)=T(0)exp(0.24t), with T(0)=816mil
M(t)=M(0)exp(0.24t), with M(0)=101mil
Our first calculation is based on the admittedly ad-hoc assumption
that India can't support a population more than double the present one.
The time for population to double is obtained by solving T(t)=2T(0),
and we get t=2.89. Since we are measuring time in decades, this is about 30
years. Now we find
that M(2.89)=262mil, while the total will double to 1632mil, and so the
Muslim fraction will be only about 16%.
Now let us look at what it would take for the Muslim fraction to reach 25%.
The relevant equation is:
M(0)exp(0.33t)=0.25T(0)exp(0.24t)
Solving for t, we get t=7.81, which is about 80 years. Now, in this time,
the total population of India would have increased to 5.3 billion,
while the Muslim
population would be about 1.3 billion! In other words, India would be
supporting as many people as the entire Earth does today, while the Muslim
population would equal that of China (currently). It is worth noting that
the final numbers really depend only on the 0.33/0.24 ratio of the two
growth rates. If the growth rates slowed down, but kept the same ratio,
it
would take longer to get to the final point, but the final population numbers
would be the same!
Notes
1. Our assumptions of constant rates of growth for the total and the Muslim
populations are clearly contradictory, since, as the Muslim proportion rises,
it will cause a change in the rate of growth of the total. If we break down
the analysis further as total = hindu + muslim, solving the equations takes a
little longer but the final numbers hardly change.
2. I emphasize again that the key numbers here are not the number of years it
would take for these events but the incredible increases required in the
two populations.
3. The assumption for our first calculation finds some support in an article
in the Sept 8, 1997, issue of Outlook magazine. On page 80, "demographer
and social scientist" Leela Visaria is quoted to the effect that the 2-child
norm would stabilise the population at 1.7 billion by about 2070.
