Last June a United Nations report predicted that the world’s population – now at 7.6 billion – was likely to increase to almost 10 billion by 2050 and to 11.2 billion by 2100. Now a Vienna based group of demographers have calculated that by 2070 the world’s population will reach ONLY 9.5 billion. This has been hailed as good news. Jesus Crespo Cuaresma from the Vienna University of Economics and Business has even concluded that “we can be richer without having to produce more” and that global environmental quality will improve.
The world’s human population is, in fact, already far above its optimum. We can see this everyday in our overcrowded cities. There are certainly some goods that can be multiplied to keep up with a growing population. But there are others that cannot. The artifacts and monuments of our cultural parts, for instance, cannot be reproduced at will. Mass tourism is in the process of transforming and destroying much of that heritage. And it is not obvious that the political and social forms of the past can be adapted to an ever-growing population. Mass democracy is not really democracy anymore.
The Stanford biologist Paul Ehrlich who 50 years ago wrote the controversial book, The Population Bomb, with his wife Anne, has suggested that the world’s optimum population is less than two billion people – 5.6 billion fewer than on the planet today. The question is whether and how we could ever get back to that number. We can think of some horrible ways in which this might happen. Ehrlich says: “To start, make modern contraception and back-up abortion available to all and give women full equal rights, pay and opportunities with men. I hope that would lead to a low enough total fertility rate that the needed shrinkage of population would follow. [But] it will take a very long time to humanely reduce total population to a size that is sustainable.”