When discussing possible limits to human ecosystems, IIER is regularly meeting with individuals and organizations promoting actively planned and managed de-growth as a possible solution. This approach comes in various flavors. Some suggest an active reduction of rich countries' energy use and consumption, while others point out that there are too many people on our planet, and that we have to reduce or reverse population growth in order to prevent a collapse in the near future. Yet irrespective of individual focus, organizations promoting de-growth either suggest a path of voluntary reductions of consumption by individuals or wish for governments to act by mandating behavioral change or by establishing incentives to drive their de-growth objective.

IIER research suggests that all those de-growth approaches will not be successful at an aggregate societal level, at least not before reality enforces de-growth when economic expansion is no longer possible. Although small groups of people actually might sign up, societies as a whole likely won't. We see three key reasons for our skepticism: evolution, substitution effects and financial markets locked into a growth model.

Evolutionary experience does not support giving up resource use

With the exception of the past 250 years of fossil fuel use, the history of humans and all other species has mostly been one of scarcity. Environmental constraints forced humans to spend most of their time on finding and growing food and on managing basic protection from nature and competitors to ensure survival. For at least half of today's global population this is still their predominant reality. In a world of scarcity, some species store surpluses, including us humans, but mostly with the focus on bridging near-term risks or breaks in vegetation periods due to cold, dry or rainy seasons. Longer-term storage was and still is risky and steeply discounted (non-financially), for many reasons, among them the risk of destruction of reserves, the risk of theft or the risk of not having access to reserves when they are needed. Behavioral science has demonstrated multiple times that human decisions very steeply discount future versus current rewards. Available research also suggests that it is irrelevant whether this decision relates to day-to-day goods or spending for luxury items.

From our perspective, it seems unrealistic to expect changes in this pattern of short term resource consumption that has developed over the course of millions of years and has been overwhelmingly successful for many species, including our own. Asking a majority of people to save resources for the future goes against well-established subconscious decision-making patterns.

Individual reductions do not change total use

While we are convinced that on average, the above holds true for humans, the pattern described doesn't necessary apply to every individual or even entire groups of the world's population, as there are wide variations in preferences, with individuals or entire groups significantly deviating from the average. In each Western society, people can be found who deliberately reduce their consumption. In a society with significant overall resource surpluses, people who actively lower their own economic and ecological footprint might get by very well, because their relative status - which is typically above average - allows them to make those reductions without reaching limits that risk their well-being. On the other extreme, for someone who might not make it through the winter without the extra calories from a non-sustainable slash-and-burn farming approach, cutting back is not an option.

There are even movements promoting one-child-only policies. Here, today's small health risks for newborns and small children in OECD countries, combined with expectations for government-supported pensions, make it feasible to raise a family with only one child without taking too much risk of impairing one's future. In societies where (child) mortality is higher and  no pension system exists, children are investments into future well-being as well as carriers of the parents' gene pool, supporting a key evolutionary objective of any living being.

As long as we still live in a world where significant portions of the population are struggling with basic food and safety issues that threaten their and their children's survival, consumption given up by one group or country will very likely be compensated by someone else. Even within societies, consumption reduction or savings of one group often shift to another part of the population, for example if a good is less desirable to one group and becomes cheaper, other groups will have easier access. Equally, reducing the number of children a "responsible" group raises will - ironically - even change the world to the worse from the perspective of the promoters of this population reduction, as those people who act less "responsibly" will over time obtain a larger share of the future population when compared to those who followed the promoters' claim.

Financial markets don't allow for shrinking economies

One of the key challenges of any de-growth approach is that today's financial markets are not designed to operate in a world of shrinking outputs. Consistently shrinking markets will likely have a number of unwanted consequences: the impossibility to serve and pay back credit for individuals, companies and governments alike, significant problems to generate new credit for investments into the future, heavy losses on debt, stocks and thus on future return and pension expectations of almost everyone. Our societies are basically locked into growth mode, and deliberate action to stop further expansion would yield very unpleasant consequences. This is another - strictly rational - reason why many people are unwilling to look at a future built on less economic output.

Reductions make no sense for individuals

The above realities create a paradox: while societies and the world as a whole desperately require us to reduce our footprint, each individual and each small group will derive no benefit from being the first to listen to that call. To the contrary, as long as others continue their way of using resources, a "responsible" group will be at an evolutionary disadvantage once societies run into problems. They will have less reserves and less children to support them once they need that support.

Our approach - expect no change unless mandated by reality

The ultimate consequence IIER derives from these findings is that we humans - for well established reasons - will not adjust our behavior at a societal aggregate level before we are forced to do so. We may find this tragic or regrettable, but ignoring this reality might drive us to incorrect conclusions. While we wish it would be different, we have come to the understanding that we should look at a future where largely unchanged societies run into resource constraints, because this is far more likely than any other more benign scenario involving deliberate changes before resource or financial market limits inhibit further expansion. This is why we focus our research on understanding those limits and what can be done to mitigate the consequences once they will be reached, and on the question of how to address the resulting problems when they become apparent to most people.