Demographic Shocks: the View from History

Demographic shocks convey the idea of a sudden change in those factors, external or exogenous to the demographic system, that affect mortality, fertility, or migration. Famines and epidemics, wars and displacement of people, can be seen as external disturbances to the normal functioning of a demographic system. Malthus renamed them “repressive checks” and made them endogenous to the system—the inevitable consequences of unsustainable population growth. Under a traditional demographic shock, mortality suddenly goes up, fertility goes down, mobility explodes, families break down; the aftershock, however, implies changes that counter the initial consequences. In other words, a steady or semi-steady state is broken and populations struggle to recover the equilibrium. This paper could limit itself to drawing on the abundant literature on the subject of shocks, both historical and contemporary cases. However, confining the discussion to this definition of shocks appears to be a limitation on the wider scope of the conference, which includes the consequences of long-term changes such as aging or international migration, whose current levels and trends appear to be unparalleled in the past. Indeed, they are defined as “seismic shifts,” and seismic derives from the Greek “seismos” or earthquake, so the idea is that we are going to experience an earthquake in slow motion, of which we already perceive the early subterranean rumblings. My task becomes more difficult because I am required to deal also with the long-term, profound changes, which somewhat parallel those in store for the future. The paper will basically deal with four issues. The first one puts