Superlongevity Without Overpopulation
forced by changing tastes resulting from improved education.
The revenue vs. expense equation for extra children further
shifts toward having fewer offspring as populations become
urbanized. Children cost more to raise in cities and can pro-
duce less income than in the country.
Fertility declines for another reason: As poorer countries
become wealthier, child mortality falls as a result of improved
nutrition, sanitation, and health care. Reduced child mortal-
ity in modern times can come about even without a rise in
income. People in poorer countries are not stupid; they adjust
their childbearing plans to reflect changing conditions. When
child death rates are high, research has shown that families
have more children to ensure achieving a given family size.
They have more children to make up for deaths, and often have
additional children in anticipation of later deaths. Families
reduce fertility as they realize that fewer births are needed to
reach a desired family size. Given the incentives to have fewer
children as wealth grows and urbanization proceeds, reduced
mortality leads to families choosing to reduce family size.
Economic policy helps shape childbearing incentives. Many
of the same people who have decried population growth have
supported policies guaranteed to boost childbirths. More than
that, they boost childbearing among those least able to raise
and educate children well. If we want to encourage people to
have more children, we should make it cheaper for them to do
so. If we want to discourage fertility, or at least refrain from
pushing it up, we should stop subsidizing it. Subsidies include
free education (free to the parents, not to the tax-payers), free
child health care, and additional welfare payments to women
for each child they bear. If parents must personally bear the
costs of having children, rather than everyone else paying,
people will tend to have just the number of children for whom
they can assume financial responsibility.