I often have this thrown in my face. You again, telling us that we should consume less to become more sustainable. You overlook things! Like population growth. If we would just reduce the size of our population, we would not have to make such big sacrifices such as lower consumption or a decline in economic activity, would we? Sorry, but no.

According to the UN’s most recent population projection, there will be 9.7 billion of us in 2050, while in the next few months we will pass the 8 billion mark. Population growth in the years ahead will be mainly due to the increase in wealth in recent decades, so it continues, albeit at a slower pace. And that is also the first reason why population reduction is not a quick route to becoming sustainable. It takes decades before such a policy takes effect. We don’t have that time.

Furthermore, population growth tends to be concentrated in the poorer parts of the world. And the impact on the environment of a baby that is born in a poor region is 5 to 14 times less than that of the arrival of a new little citizen in a prosperous environment. So, if it is useful population decline that we are after, what we need is for the population in our part of the world to contract and not in countries where the population is growing rapidly. And more than that: in poorer regions more wealth would probably be the best way of slowing down population growth, because investments in social security and education are the best forms of contraception. Fertility rates decline if people are wealthier and especially if social arrangements like retirement benefits and education improve.

There are countries where the population is about to start shrinking. China, Germany, and Italy, for instance. Excellent, you would think. But: this is seen as an economic problem. A smaller population with more elderly people means that there are fewer hands to do the work and - most of all - pay taxes. If the population is declining, we need to fundamentally overhaul the economy and start considering it in the same way as the concept of less consumption per person: ‘shrink thinking’. Or, in other words, adjust the economic machine from being growth dependent towards growth agnostic and adaptive to decline - a post-growth economy.

And that brings us back to less wealth, including the clever guy who argues that technology will save us and will deliver us ever-increasing sustainable economic growth. Unfortunately, there is hardly any evidence to support this.

I suggest we keep trying to do everything we can: sustainable innovation, fewer people, but also preparing ourselves for lower material wellbeing. For instance, by making our government budgets and corporate funding less dependent on growth. And the same should go for business models and our own plans for the future. And if we do that, we may well find that it is quite possible to consume less and still be happy.

I am not saying we must do any of these things. But arguing that we do not have to change anything because population growth is the biggest problem is just not on. If we keep coming up with excuses for not changing our own behaviour, we will get that population decline for free with a cocktail of misery.

This is a translation of Hans Stegaman's column in Het Financieele Dagblad, published 26 July 2022.