This article from CleanTechnica is a great example showing that unlimited growth cannot continue indefinitely. There are no known cases of perpetual unlimited growth anywhere in the universe. What’s makes us think we can do better?
The CleanTechnica article notes that the economic crisis in the USA has lessened that country’s environmental impact. The reason is twofold. First, there is less consumer demand and fewer consumers who can afford energy (e.g. air conditioning); second, the lessened consumer demand has caused businesses to scale back their activities, which acts as a multiplier effect. Together, these have lowered the base load of electricity needed to keep the country running. Thus, even though the summer has been very hot, there have not been the blackouts we might have had five years ago, because the base electric load is low enough that the spikes caused by the hot weather are not overwhelming the grid.
I see this as a negative (damping) feedback loop connecting the economy and the environment. That is, as the economy grows, so does its environmental impact. But increased environmental impact puts a strain on the economy (think of all the money needed to mitigate environmental impact – money that could have been used for other, more constructive purposes than just fixing things that we’ve broken; think of increased health care costs due to pollution). Eventually, the economy breaks under that strain. Unlimited growth stops, even reverses. And as the economy slows, the environmental impact decreases, easing the strain on the economy, allowing it to eventually grow again.
This is just one of hundreds, if not thousands of loops that exist between activities, be they natural or artificial. Some of those loops are positive feedback loops: increasing one increases the other, which increases the one even more. An example of positive feedback is what happens when you bring a microphone too close to a speaker. These loops can be beneficial, but in extremis they are always harmful. You can make some interesting noises moving a microphone close to a speaker, but if you leave it there long enough, you’ll blow out the speaker and possibly your eardrum too. Another good practical example of a positive feedback loop is compound interest. The more money you invest, the more money you make, which if you reinvest enough will always increase the value of your investment more and faster. Eventually, you end up having the entire world economy in your bank account (which obviously isn’t going to happen). At 6% compounded annually, every dollar you invest will become $4 in 25 years, $18 in 50 years, $339 in 100 years, and $115,125 in 200 years. (Note the exponential growth.) Another positive feedback loop is the downward spiral of the quality of education. The worse the education that people receive, the less able they will be to make informed voting decisions, which will result in less capable elected officials, who will likely damage the educational system even further. Positive feedback loops aren’t necessarily beneficial.
Negative feedback loops are the converse of positive ones: increasing one thing increases the other, which in turn decreases the one. Population and food form that kind of a self-balancing loop (within certain limits). As a population of organisms increases, so does the need for a food stock. At some point, the population will exceed the natural size of the food stock. Population will begin to shrink because the organisms simply cannot get the food they need to survive and reproduce. Inflation is a positive feedback loop, but that works against interest rates to create a broader negative feedback loop. Inflation has a negative effect on the value of the money that you’re accumulating via compound interest. The reason why governments try to keep inflation rates as close as possible to interest rates is that the two balance each other and create stability.
I mentioned that there are limits on self-balancing, negative feedback loops. These are very important because they determine whether the system will survive the changes caused by the elements of the loops. Going back to the population-and-food example: if the population of organisms increases fast enough past the point that the feed stock can support, and does not drop down quickly enough, then the feed stock will be destroyed, which in turn will destroy the population too. So it is not only the amount of change that matters, but also how fast the change comes about. That is, every system is able to absorb changes only at less than some maximum capacity of resilience defined by the characteristics of the system elements and how they interact. Once those limits of resilience are passed, the system will inevitably break down.
Unlimited growth is a positive feedback loop that simply cannot be maintained indefinitely. There is no natural system – not even the universe itself, as far as we can tell – that undergoes perpetual unlimited growth. In other words, everything dies sooner or later.
It is utterly insane – it’s an abomination – for humans to think that they can possible control nature enough to break this fundamental characteristic. We may, at some point in the distant future. But for now we haven’t got the first clue how to do that, no matter what the politicians, economics, and bankers will tell you. We need to design systems such that they will expire gracefully. Right now, our systems don’t expire at all; they implode (if we’re lucky), wreaking incredible havoc on everyone involved.
Although the economic “downturn” has caused terrible harm to many, many people, we have been lucky because it wasn’t as bad a failure as could conceivably happen. Think of the 2003 blackout, the root cause of which were some untrimmed trees, and which affected some 55 million people. Imagine if the financial system were to vanish – like the power supply did – even for only a short time. I’m not trying to be alarmist – I am simply offering an example of the kind of failures that brittle (i.e. hyper-efficient and therefore not very effective) systems can suffer.
This is what happens when we try to beat nature; it will always find a way to get even. Instead of just fighting against these natural characteristics of systems, we need to start designing systems that work with these characteristics. We need to understand that everything will end eventually, and we need to design for that death in a way that we can adapt when it happens, instead of rigidly – stupidly – trying to resist the inevitable.