Ever since Thomas Malthus argued 200 years ago that population growth was outstripping “the ability of the earth to produce the food required for man's survival,” we've seen a wave of Cassandras worry that humanity is exhausting the planet's carrying capacity.
Neo-Malthusian thinking influenced 20th-century works such as Paul Ehrlich's 1968 book The Population Explosion and the Club of Rome's 1972 book The Limits to Growth, which predicted that civilization would end “within the next 100 years.” In his 1973 book Toward a Steady-State Economy, economist Herman Daly argued for resistance to economic growth for the sake of the environment.
Climate change is once again provoking such sentiments. But the prescription that economic growth must stop is as wrong as when the pessimistic Reverend Malthus predicted that population growth would outstrip the planet's capacity to produce food, and that famine, war and plague would be needed to bring human population back to a sustainable level.
“Degrowth” is a brand name for neo-Malthusianism, but it ignores the ingenuity and innovation that have enabled humanity to repeatedly overcome the ecological constraints identified by Malthus, Ehrlich and others. Degrowth advocates ignore the basic lessons of history: the world has not experienced growth for hundreds of years. To be economically successful at certain times in the Middle Ages, for example, required plundering your neighbors. Trade was zero-sum. The result was centuries of conquest and subjugation.
Malthus made his prediction at a time when Britain and the rest of Europe were about to enter a second century of unprecedented economic growth that freed much of humanity from suffering and vastly improved health and well-being. Ehrlich's prediction came at a time when the Green Revolution in agriculture was saving hundreds of millions of people from starvation.
Growth has created a world where one person's gain does not come at another person's loss. Consensual politics and democracy would not be possible without growth. It will be interesting to see how Daly and his followers' pledge to end growth (or reproduction) to save the planet will be received in the bustling but impoverished megacity of Lagos, Nigeria.
Yet degrowth is coming back into fashion: its advocates include progressive journalist Naomi Klein, Swedish activist Greta Thunberg and even Pope Francis, and at least one European university now offers a master's degree in degrowth.
The truth is that degrowth will not solve climate change, even if it is unlikely to be forced. Carbon emissions from economic growth can be understood as the product of four factors: population growth, growth in economic output per capita, changes in the amount of energy required to produce the economy, and changes in the amount of carbon dioxide emitted when energy is consumed.
The US Energy Information Administration projects these variables through 2050. The inescapable conclusion is that zero growth in gross domestic product will do very little to reduce emissions: even if per capita production remains at 2023 levels through the middle of the century, humanity will be 26 billion tonnes of carbon dioxide short of its goal of net-zero emissions by 2050.
The climate effect would be even smaller if we simply stopped growth in the rich countries, while poor countries like Nigeria continued to grow and hoped that one day they would achieve the economic prosperity that the rich countries enjoy today. In this scenario, the world would fall 38 billion tonnes short of its mid-century carbon dioxide emissions target.
Reducing emissions to safer levels would require deep degrowth: keeping carbon dioxide emissions to below 10 billion tonnes per year in 2050 would require inducing a recession that reduces global GDP per capita by about 5% per year – more than the losses caused by the 2008-2009 Great Recession.
Reducing the carbon emissions the global economy produces requires massive new green energy infrastructure and new clean technologies — in other words, growth and innovation. The Energy Information Administration assumes that a world with rapid economic growth will require about 13 percent less energy per dollar of GDP in 2050 than a world with slower growth.
Of course, GDP is not a true barometer of a civilization's well-being. Those who advocate unlimited growth ignore the damage it does to the environment and human health. But it calls for mitigating the damage, not abandoning growth altogether.
The prophets of degrowth have little to no response to the most basic questions about their prescriptions. Degrowth evangelist Kohei Saito proposes “degrowth communism” but seems unaware that countries like Albania and North Korea are already experiencing it. Not surprisingly, most degrowth advocates were born into societies that were already rich, not those that tried and failed to get by without growth.
