After the Spike review: Provocative new book says we must persuade people to have more babies

After the Spike
Dean Spears and Michael Geruso (Bodley Head (UK); Simon & Schuster (US))

Four-Fifths of all the humans who will ever be born may already have been born. The number of children being born worldwide each year peaked at 146 million in 2012 and has been falling overall ever since. This means that the world’s population will peak and start to fall around the 2080s.

This fall won’t be gradual. With birth rates already well below replacement levels in many countries including China and India, the world’s population will plummet as fast as it rose. In three centuries, there could be fewer than 2 billion people on Earth, claims a controversial new book.

“No future is more likely than that people worldwide choose to have too few children to replace their own generation. Over the long run, this would cause exponential population decline,” write economists Dean Spears and Michael Geruso in After the Spike: The risks of global depopulation and the case for people.

This, you might think, could be a good thing. Won’t it help solve many environmental issues facing us today? No, say the authors. Take climate change: their argument isn’t that population size doesn’t matter, but that it changes so slowly that other factors such as how fast the world decarbonises matter far more. The window of opportunity for lowering carbon dioxide emissions by reducing population has largely passed, they write.

Spears and Geruso also make the case that there are many benefits to having a large population. For instance, there is more innovation, and economies of scale make the manufacture of things like smartphones feasible. “We get to have nice phones only because we have a lot of neighbors on this planet,” they write.

So, in their view, our aim should be to stabilise world population rather than letting it plummet. The problem is we don’t know how, even with the right political will.

While some government policies have had short-term effects, no country has successfully changed long-term population trends, argue the authors. Take China’s one-child policy. It is widely assumed to have helped reduce population growth – but did it? Spears and Geruso show unlabelled graphs of the populations of China and its neighbours before, during and after the policy was in place, and ask the reader which is China. There is no obvious difference.

Attempts to boost falling fertility rates have been no more successful, they say. Birth rates jumped after Romania banned abortion in 1966, but they soon started to fall again. Sweden has tried the carrot rather than the stick by heavily subsidising day care. But the fertility rate there has been falling even further below the replacement rate.

All attempts to boost fertility by providing financial incentives are likely to fail, Spears and Geruso argue. While people might say they are having fewer children because they cannot afford larger families, the global pattern is, in fact, that as people become richer they have fewer children.

Rather than affordability being the issue, it is more about people deciding that they have better things to do, the authors say. As we grow richer, we are more reluctant to abandon career and leisure opportunities to have children. Even technological advances are unlikely to reverse this, they say.

On everything other than the difficulty of stabilising the population, this is a relentlessly optimistic book. For instance, say the authors, dire predictions of mass starvation as the world’s population grew have been shown to be completely wrong. The long-term trend of people living longer and healthier lives can continue, they suggest. “Fears of a depleted, overpopulated future are out of date,” they write.

Really? Spears and Geruso also stress that the price of food is key to determining how many go hungry, but fail to point out that food prices are now climbing, with climate change an increasing factor. I’m not so sure things are going to keep getting better for most people.

This book is also very much a polemic: with Spears and Geruso laboring their main points, it wasn’t an enjoyable read. That said, if you think that the world’s population isn’t going to fall, or that it will be easy to halt its fall, or that a falling population is a good thing, you really should read it.

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