Lecture 22: Modern demographics
The next three lectures will concern modern demographics and migration in the era of
globalization. This lecture will be about modern birth and death rates and population growth, the
next lecture will be about the history of migration and the last one about migration economics and
policy considerations. It may seem odd to start with modern demography and then revert to the
history next time, but the reason is that I need the demographic theory to help explain the history.
The demographic transition
The beginning of the demographic transition is one of the indicia of the coming of the
modern world, and so it arrived at different times in different places. Modernity, and, with it, the
demographic transition, began in England, the English colonies in North America and in
northwestern Europe in the late eighteenth century, spread to Germany and Scandinavia in the
middle of the nineteenth century and to southern and eastern Europe at the end of the nineteenth
and the beginning of the twentieth century, with the rest of the world following in the decades
after World War II.
On the Y-axis we have birth rates and death rates. Time is the x-axis.
start back here in traditional society. Birth rates are high: the average woman might have eight or
ten children. Remember that almost all traditional societies are rural, and children are assets on a
farm: they can help with the farm work. Death rates are also high, both because of high
childbirth mortality among women, high infant mortality and general high disease rates due to
such things as bad drinking water, poor diet, exposure to the elements and lack of medicine. So
birth and death rates are both high, and the difference between them, population growth is very
small and the population itself is quite low. We can call this Phase 1.
Now we enter Phase 2, the transition to modern society. There’s a lot that can be done to
bring down the death rate fairly quickly: clean drinking water, medical care, elementary OB-
GYN. And it is done. There is virtually no sales resistance to clean water and decent medical
care. Very few people want to die or want the members of their family to die. There’s
occasionally some distrust of modern medical practitioners to be overcome--there was a story last
year about some religious nut who thought polio immunizations spread polio, or something like
that--but the thing about science is, it works. The people who get the immunizations don’t get
polio and the people who don’t do. This tends to convince people to accept the new techniques,