Interview with Hervé Le Bras: "Population in itself is not evil. Consumption is the real issue."

• © DR

Hervé Le Bras, historian and demographer, is Directeur d’études at the Ecole des hautes études en sciences sociales. He was one of the participants at the last session of "21st century talks," held at UNESCO on 22 May.

Interview by Agnès Bardon

Forecasts of population trends are often proven wrong. Is the science of demography bound to err?
We are dealing with projections, not predictions. Demographers do not believe that projections will come true. They are policy-oriented depictions of possible outcomes. Alfred Sauvy, a famous French demographer, used to say that we must “foresee to not see”. This means that projections serve the purpose of warnings. They present us with whatever risk might occur if mankind does not act and thus help change the way we behave. It is the very same with climate change previsions. Nobody wants to actually see the oceans rise: what you want is to prevent it or to mitigate it.

Whether we fear an out of control overpopulation of the planet or whether we dread the prospect of depopulation, it seems that demography is about always about a bleak future. How do you explain this?
Demographers’ tales never have a happy ending. That is because population science is one of the last havens of eschatology, a belief in the end of times and in the relationship of man’s fate to Judgment Day. In the past, William Petty and Isaac Newton computed demographic previsions to forecast the end of time. This idea--that demographics hints at the end of time--can also be found in Malthus’ writings. Nowadays, our ideas are different but we somehow inherited a certain lure for catastrophe.

In the 1970’s, demographic explosion was the fear of the day. For some years now, though, UN previsions have clearly reported a decrease. Why?
First of all, this fear of a demographic explosion is recent: it started in the wake of World War II. Traditionally, depopulation is what has been dreaded. Higher growth estimates have peaked in the 1970’s with forecasts announcing a world population of 12 billion in 2100. But, according to current projections, the figure should be 9.2 billion in 2050. No one had anticipated that fertility rates would decrease, especially in developing countries. In Tunisia, for instance, the fertility rate is now less than two children per woman. Iran’s situation is even more telling. In less than fifteen years, the rate has dropped from six to two children per woman. Many explanations can be proposed afterwards, from dwindling oil revenues to increased levels of education for Iranian women, but the bottom line is that such trend reversal are hard to explain. Likewise, no one knows why the baby boom happened.

Is this projected decrease a good thing?
It is neither good nor a bad: we can just report on it. Commenting on those trends would be nothing more than a moral judgment. The problem, though, is with our consumption styles. More and more, developing countries vie to emulate the American Way of Life, which is very worrisome for the future. It seems to vindicate those who, thirty years ago, deemed population growth to be the source of all evils. But population in itself is not evil, it is just a multiplier. Consumption is the real issue.

• 29-05-2007