David Kingman argues that commentators have become too caught up in arguing about the appropriate size for the Earth’s population, when what really matters is the age structure of the population in individual countries
It seems fitting to discuss population around Christmas time, bearing in mind that the main action of the nativity story is inspired by an ancient census – proof that human beings have always had an obsession with counting their own number. This interest extends right up to the present day, and could be seen most visibly in the storm of debate provoked in October by the almost simultaneous announcement that the global population would reach 7 billion within days, and that Britain would be home to 70 million people by 2027.
This was unsurprising. Concern about global population has been bubbling away beneath the surface of society’s popular discourse for years, occasionally breaking through whenever a new series of projections drag the issue into the spotlight.
The Malthus effect
It really began with Thomas Malthus, the Anglican priest who wrote the famous Essay on the Principle of Population, which went through six editions following its original publication in 1798. The book has its origins in an obscure philosophical debate: Malthus offered a series of arguments which refuted the claims made by utopian social thinkers, such as William Godwin, that human society was perfectible, presenting his view that in a perfect society, man would have no barriers to reproduction, so the number of inhabitants would go on increasing until it had provoked a famine or civil war.
Malthus was the first to argue that exponentially expanding human populations were unstable. He reasoned that if the population is to expand, the supply of food must expand in parallel in order to avoid a famine; yet there is a crucial barrier which prevents this. Population expands geometrically, while food supply can only increase arithmetically. Another way of thinking about this is to say that each increase in the population has momentum: it contributes to a further increase (if a family has three children, and they each have three children, then the population keeps getting bigger with each generation), while each increase in the food supply makes further increases more difficult (if grain yields increase 10% then it is harder to match that the following year because a bigger actual increase is required for the amount of grain to go up by 10% again).
Malthus was heavily criticized in his own time, although his ideas have remained influential. However, the accelerating population increases of the 19th and 20th century, which have dwarfed anything the human race had experienced in the period before Malthus wrote his book, have led to further questioning of his theories. Global population was less than 3 billion in 1950,yet it has reached 7 billion in little over 60 years without a major collapse occurring.
His lasting legacy, however, has been that whenever the spectre of global population growth rears its head, people are always quick to describe it as a crisis, often in hysterical tones. For example, in covering the new prediction that global population could reach 15 billion by 2100, the Daily Mail decided to lead with “Experts say urgent action is needed to curb growth and save the planet’s resources”, and they reused a quote given by Roger Martin, the chairman of Population Matters, during an interview with The Observer: “Our planet is approaching a perfect storm of population growth, climate change and peak oil.”
Population Matters is just one of several think-tanks and pressure groups which argue that unregulated population growth is mankind’s next catastrophe. Also prominent in Britain are MigrationWatch UK, whose chairman, Sir Andrew Green, is often put in front of the cameras whenever a population story appears.
Among organizations with a global focus, America has its own pressure group, World Overpopulation Awareness, while the UN Population Division and other, more research-led NGOs such as the Population Reference Bureau have a history of advocating family-planning strategies, showing how institutionalized Malthus’ legacy has become.
The sideshow of global population
What all this misses is that global population is a distraction when debating the really big problems caused by demography.
Simply put, there hasn’t yet been a crisis caused by global overpopulation, and it’s unlikely there ever will be. For a start, no one can decide what constitutes overpopulation. Some campaigners argue that Africa, with its teeming slums and seemingly constant famines, is overpopulated. In the popular imagination, hordes of people threaten to overwhelm the tranquil beauty of the rainforests and national parks in their quest for food and water, leaving behind land as desiccated as the Sahara.
There are others, though – mainly environmentalists – for whom the situation is reversed. Africa may be home to a billion people, but most of them consume very few resources, the result of millions of lives lived without the Western conveniences of cars and electricity. Just to give one example, it has been estimated that the average American consumes the same amount of energy every 28 hours that a typical Tanzanian uses in a year. The logical conclusion of such arguments is that America is the country most in danger of a population crisis, as the staggering volume of natural resources it needs to supply its way of life far outstrips the nominal population weight of its relatively meagre 300 million people.
Even if we one day reach a point where the majority of citizens in what is currently the developing world can live a life of Western-style consumerism (a goal towards which progress in many parts of the globe remains agonizingly slow), the likeliest outcome is that markets will come to the rescue. Whenever shortages of a resource start to bite, Western consumers will feel the pinch from raises in price, which will incentivize the consumption of cheaper alternatives. Increases in price for gas and coal, for example, have the impact of making alternative fuel sources more economical by comparison, so in the long term they could usher in a new age of lower reliance on fossil fuels. While there could be small pulses of anger over higher resource prices – similar in scale to the fuel protests that gripped Britain back in 2000 – the fears harboured by doom-mongers of worldwide civil unrest and starvation seem very unlikely to happen.
In any case, attempts to encourage people to have fewer children invariably become entangled with philosophical debates over the nature of reproductive rights. Should people be allowed to just have as many children as they can afford to support materially? Or should numbers be limited, in order to reflect the costs of having more children on the environment? And who would have the right to impose such limits? China, obviously, has gone down the path of population controls, but this is usually depicted in the West as a severe human rights violation.
For all the concern expressed by the size of the global population, there is an issue that is likely to have far larger ramifications for peoples’ everyday lives, often without them realizing: the age structure of national populations.
This always has a substantial impact on multiple facets of a country’s national life. Countries with a large proportion of young people, particularly young men, are likely to have higher levels of crime and social unrest (a phenomenon borne out by the youth-led revolutions of the Arab Spring earlier this year). Places where there are large numbers of children and young people tend to have higher social spending because there are more people consuming government services (the so-called “dependency ratio” effect), while economies that contain large numbers of young workers, but relatively few older people or children, can usually grow quickly by reaping a “demographic dividend”.
If the population structure of a country changes, then so does the country. The baby boomer generation is often credited with completely changing the nature of youth, simply because never before had so many young people been born and survived infancy. In the 1960s and 70s, for the first time there were enough adolescents alive at once for them to represent a significant target for advertisers; the result was the societal mythologization of youth, with the adoption of the word “teenager” to describe people at this stage of life, and the wholesale promotion of youth culture in pop music, “teen” films and fashion, which continues to this day.
When it was announced in October that Britain’s population was expected to reach 70 million at a faster rate than previously expected, the main focus was on immigration, and how much of the increase would be due to people coming in from abroad. This is an interesting discussion to have, although again it put the focus on the wrong issue. This is partly because it is very difficult to forecast: migration tends to rise and fall in line with demand, so we have to predict reliably how much additional labour the economy will demand over the coming years, which is far from easy.
We also end up having to make arbitrary distinctions between what constitutes British and “foreign”. The British-born children of immigrants tend to have higher birth rates than the national average, so immigration usually increases the national birth rate as well. This phenomenon causes a problem, because at some point the statisticians need to draw a line between immigration and “natural increase” (the population increase supposedly caused by the “indigenous” birth rate), which is extremely haphazard. After all, even if someone only has great-grandparents who were born overseas, their life is still a product of immigration, meaning it is extremely difficult to make the kind of firm cut-offs (“52% of population increase caused by immigrants”) that commentators like to dwell on.
Population ageing, and particularly its impacts on the younger generation, tends to receive less attention than immigration. Yet it is fundamentally more important, because it is much more certain. When the October projections said that two-thirds of the population increase between 2010 and 2035 will be caused by immigration, it was just that, a projection. However, when they also said that the number of people over 75 will go from 4.9 million to 8.9 million, they were much more likely to be accurate.
This is because the migrants are people in other countries who may or may not come over. With ageing, virtually all the people included in the projection are here already, and only a few thousand of them are likely to move abroad, while fewer than in any previous generation will die; 2035’s over-75s are, to a great extent, just today’s people in their fifties with slightly greyer hair. As population ageing has costs – mostly in the form of pensions and healthcare – which the OECD has estimated will be running at £80 billion per year more than they are now by 2050, we need to find ways of reforming our systems for retirement and elderly care so that these costs can be managed.
Is immigration the answer?
One of the main costs of ageing will come from pensions, both the state pension and those for retired public sector workers, which are all run in what are known as “unfunded” schemes. Essentially, this means that even though we can predict what the costs of these will be, no money is ever put aside to pay for them; instead, those who are currently working pay for the unfunded pensions of those in retirement through the national insurance system, in the expectation that the same will be done for them when they retire.
This system works fine if the number of people in retirement at any one time is relatively small, and the number of workers keeps growing, as it has done for most of the lifetime of these pension schemes so far. However, if the number of retirees increases dramatically – as it is predicted to – while the number of workers remains flat, then the workers have to pay more through taxes to prevent the schemes from running out of money; a move which obviously has economic and social repercussions.
The upshot of all this is that we’ve been having the wrong debate. We’ve responded in the wrong way to both the national and international population discussions, allowing it to become largely accepted that smaller populations are what we want. The Independent was guilty of this back in October:
“The steady growth [in population] has financial implications for the country because of the growing pressures on schools, housing, the National Health Service and the social care budget.”
This says nothing of the financial implications if our working-age population is not growing, which would be equally severe, with fewer people to meet the increasing costs of old-age care, and to pay off the vast liabilities the older generation has accumulated in their unfunded pension schemes. If we want to be able to afford those, and deliver prosperity for our children, a larger working population is exactly what we need.