When we think about acting responsibly towards the environment a lot of space is given to recycling, using energy saver light bulbs, abolishing plastic shopping bags and plastic water bottles or having shorter showers. However, if you analyse how much CO2 each of those measures save it’s actually not that much. If you would add up all of these and put on top going car-free and vegan, avoiding air travel and converting your energy to solar, the sum total would still only be a fraction of the one single measure of bringing one less child into the world.

Having a single child less will save 58 tonnes of CO2 each year for each parent’s life. Here’s the report https://www.theguardian.com/environment/2017/jul/12/want-to-fight-climate-change-have-fewer-children.

This powerfully drives home the point that if we want to survive as a species and biosphere we need to reduce global population. Since decades the UN waffles on about us soon reaching peak-humanity (the point from which population growth becomes negative). But just recently the forecast was again upgraded from 9.5 to 11.4 billion and this is on top of a 40 year history of upgrades. Already in 1999 humanity’s demand of planetary resources exceeded Earth’s supply capacity by 20% (Wackernagel, M.; Schulz, N.B.; et al. (2002).

In 1999 our population was 6 Billion. Take 20% off (the amount that we exceeded), that’s 4.8 Billion. Wackernagel and Schulz calculation, however, does not even take into account fossil fuel depletion, which increases our carbon footprint one-hundredfold.

If we are really generous for a moment and waive the hundredfold increase (otherwise it just makes the estimate too pessimistic) and simply say let’s half the 4.8 Billion number to take into consideration past fossil fuel usage. This would bring us to a carrying capacity of Earth of 2.4 billion humans. That’s roughly the number we had at the end of WW2, which was the beginning of global capitalism and the great acceleration of trade and worldwide industrialization.

I’m not too fussed whether we set the limit of sustainable population growth there at 1945 or during the 1960’s or even as late as 1970 (3.7 Billion) when Earth Overshoot Day started. The point is we as a global community are living far beyond our planetary-resource means. Taking short showers and using reusable shopping bags and water bottles is great. It’s great for giving us a warm fuzzy feeling in the belly that we did something good. But it’s not enough. We need to do more.

Each child born comes with an enormous carbon footprint. For each additional human we have to fell more rain forest and turn it into food plantations. Each additional person takes up resources that we need to share with all other species that have a right to exist as much as we do.

But there’s more to that. They do not just have a right but we actually need them. The more diverse the biosphere is the more stable it is. More and more species evolved over time to increase the stability of the biosphere, which consists of homeostasis, maintaining the parameters that guarantee life on the planet on an even level. These parameters such as temperature, PH, and/or chemical composition of soils, atmosphere and oceans are not existing accidentally but are maintained by the biomass, i.e. the total mass of all organisms on the planet. The more diverse this biomass is the better it is at doing that job.

Currently we have started a process of mass extinction of diverse life forms. Every day we are making plants and animal species extinct. As biodiversity decreases the capacity of the biomass to maintain homeostasis (evenness of bio parameters) decreases, too.

Good news is, there are actually organisms that don’t have a problem with that. There is a domain of microbes called archaea. They are amazing. They can live at the rim of deep-sea volcanos in 900 degree hot water and metabolize the emitted sulphur. They have been found hundreds of meters under the sediment of Lake Titicaca (the world highest and deepest lake in the Andes) where they would have lived without oxygen for a billion years. Their secret is that they can adapt to the most hostile of environments and the reason they can do that is that they are not specialized at all. Because of their low level of specialization, they can survive everything we do to the biosphere. To them it will be water on a duck’s back.

To turn that around, the organisms most vulnerable to the current mass die-off of species are the most specialized. The most specialized of all of those is us, you and me, homo sapiens, as we like to call ourselves. Look at us couch-potatoes and perceive the amazing bio-support-system in place by all other species. By killing off all of the other guys (since 1960 we have lost 85% of the worlds wildernesses and killed more than two thirds of all wild mammals) we are literally pulling out the rug on which we stand. We can’t live without the biosphere.

Back to the outset and the quoted article. In order to live in harmony with all organisms we need to reduce human population so that their population can again grow. This can only happen through education and choice. About a decade ago the then Australian treasurer Peter Costello stated that for the Australian economy it would be the best if each couple had three kids. He said, “One for Mummy, one for Daddy and one for the taxation office”. In the light of the above information I’d like to turn this around. For the biosphere it is better if we have less children for example one per couple. One for Mummy, one for Daddy, minus one for Planet Earth.

Don’t get me wrong. I do not have the right and do not wish to dictate anybody their rate of procreation. Neither wished Peter Costello. But his suggestion (which is still echoed today by politicians, economists and business people around the world) is that we need to grow. More GDP, more industrial output, more consumption, more expenditure, more taxes and to guarantee that all, more population. In order to continue to thrive as a species including the surrounding biological community we need to shrink all of these factors and above all, population.

The first step towards that is information and education. We need to drill through the doctrine of continuous growth perpetuated by those who run our economies. They do maintain this doctrine because they only look towards the next electoral cycle and the need to show a budget plus, growing stock and real estate values, etc. This growth, however, while it may look good in the short term, in the longer view looks to societal collapse.