Welcoming earth’s 8-billionth living person Premium

With the planet’s population set to hit a new milestone, it would be a fool’s errand to try to predict where the actual limit to human potential lies.

Representational image only. | Photo Credit: The Hindu

Around mid-November, the world will have its 8 billionth living human being, according to an estimate from the United Nations. When the milestone is reached, it will have taken the world a little less than half a century to double its population from 4 billion people in 1974. But going by current population trends, there will not be another doubling of human population any time soon. In fact, humanity’s next big challenge may well be a declining population. 

The UN projects the world’s population to hit a peak of 10.4 billion in the 2080s. That is when the negative effect of falling fertility rates on population growth is projected to kick in. Global fertility rates have declined since the 1950s, from around 4.5 births per woman to below 2.4 births per woman in 2020, and it is expected to drop below the replacement fertility rate soon. The replacement fertility rate, which is 2.1 births per woman, is the minimum required to simply maintain the human population. In many countries in the West, fertility rates have already dropped below the replacement level fertility. In fact, two-thirds of the world population lives in countries where fertility rates are below replacement rate. Even in India, the total fertility rate has dropped below 2.1 births per woman. 

Yet, amid sharply falling fertility levels and the clear risk of a shrinking human population, the consensus view today is that the human population hitting 8 billion is a cause for worry. The seeds of this fear towards rising human population were sown back in the 18th century by British economist Thomas Malthus. Malthus argued that rising human population would put enormous pressure on the earth’s limited resources and that nature would keep a check on it. Whenever human population surpassed the earth’s ability to feed them, he predicted, famines would wipe out enough people to restore equilibrium. Malthus, in effect, believed that humanity’s failure to keep its population in check would lead to poor living standards. But today, more than two centuries since Malthus’s prediction, the earth’s population is eight times what it was when Malthus made his dire predictions and living standards have improved massively. 

After Malthus, many other social scientists have come up with regular warnings about the destructive impact of human population on the planet and the limits to economic growth. Yet their predictions, just like the predictions of Malthus, have repeatedly failed to come true. The most notable among these doomsayers was American biologist Paul Ehrlich who in his 1968 book  The Population Bomb predicted that “hundreds of millions of people” would starve to death in the following decade. But, to cite one factor, the Green Revolution ensured that such a sad catastrophe would not happen.  

So, what is it about human civilisation that has ensured that population doomsayers are proven wrong time and again? The answer lies in the strong financial incentives that the market economy offers to people across the globe to preserve the earth’s scarce resources and also to extract the most out of these scarce resources. 

Role of private property 

For one, private property rights ensure that people have a strong financial incentive to take care of the resources that they own. The owner of a piece of farmland, for example, has a strong reason to ensure its proper upkeep as it is a potential source of income. Many environmentalists often argue that private ownership of scarce resources will lead to the overexploitation and the quick depletion of these resources. But the fact remains that secure property rights actually offer property owners a strong incentive to exploit resources sustainably over a long period of time in order to maximise returns. When secure property rights which are guaranteed by independent courts and police are absent, people will simply opt to plunder resources quickly. In fact, that is what causes the destruction of many natural resources today. For example, resources such as rivers and forests, which are usually under public control, tend to be damaged by terrible mismanagement. Economists call this the “tragedy of the commons”, wherein no one really has any financial incentive for the upkeep of public property. The solution to this problem usually lies in devising ways to bring these public resources under a system of common property rights.

Two, private property ownership also ensures that there is a strong financial incentive for property owners to exploit resources most efficiently. This ensures that humankind can extract more output out of the same resources, thus helping to sustain larger populations at higher standards of living. Businesses, for example, have a strong incentive to produce the most output using the least resources. This urge to save costs has been the force behind many innovations that have helped improve human productivity. Alarmists like Ehrlich also often underestimate the role that human ingenuity plays in the efficient exploitation of resources. To them, a larger population simply means a larger burden imposed on the earth to sustain. But remember that path-breaking discoveries and innovations occur more often in larger populations. A human civilisation of 8 billion people, for instance, is a lot more likely to come up with the next big cost-saving discovery or innovation than a hypothetical small global population of a few million people. 

If the squeeze comes 

None of this is to deny that there could be, at least theoretically speaking, a limit to the size of the human population that the earth could sustain. As we near that point, living costs would rise gradually to signal increasing scarcity. People in turn would respond to higher living costs by choosing to have fewer babies or settling for a lower standard of living. In other words, human civilisation would gradually adjust to resource constraints without the need for any catastrophe that wipes out millions of lives as Malthus suggested. In fact, that is already how the world adjusts to today’s resource constraints. When the price of a commodity rises, for instance, people adjust to it by making changes to their daily plans accordingly. But as the failed predictions of several population alarmists over the centuries have clearly shown, it would be a fool’s errand to try to predict where the actual limit to human potential lies.