Two Stories

My efforts to explain and project global trends in population and consumption have yielded two competing stories about the past and our potential future. With critical new insight about the second one emerging from work over the past week that may have reconciled the two, this is a good time to summarize them.

The stories are based on several key observations. First, happiness (life satisfaction) varies predictably with the amount of resources people consume, as measured by their ecological footprint, with smaller and smaller increases in happiness as consumption increases, approaching a maximum amount as any one person approaches consumption of the output of Earth's entire biosphere. Second, there is a minimum amount of such resources each person needs to survive. Third, the population of an average other species decreases linearly with the total amount of resources that humanity consumes. Fourth, global economic activity is proportional to the square of the product of population and happiness, which I interpret as transactions of artificial environments that provide happiness. Fifth and finally, in small groups life expectancy increases with consumption much as happiness does, while in large populations it varies with the total resources consumed by the group.

The first story comes from mathematically simulating "worlds" that each represent a point in time with a certain population, ecological footprint, and total amount of resources. A world can only "exist" when: (1) the resources consumed by the population is no greater than the total resources; (2) an average "person" consumes no less than the minimum; and (3) average happiness is less than the maximum. As total resources decrease, the number of worlds decreases, and the remaining worlds are clustered around more restricted combinations of population, ecological footprint, and happiness. Using historical data to identify the worlds occupied by humanity over time, it appears that as our species has consumed more resources, it has targeted the most dense concentrations of remaining worlds, with the objective of occupying as many worlds as possible without decreasing population in the process.

Behind both narratives is a more conventional backstory. All species collect and recycle energy and material, using it to exist as long as possible and to maximize the propagation of their forms over time and space. As the distribution and types of energy and material change, they adapt by changing their behavior and their form (evolving). From the perspective of members of any one species, other species either assist them, impede them, or are merely parts of their background environment that may assist or impede them later. "Assistance" can understood in economic terms as the provision of products and services, collectively considered as "resources" that include food (a primary source of energy and material) and purification of water (processing a resource for use and eliminating threats to survival), and those resources can be provided either on a continuous basis or a one-time basis. "Impeding" includes removal and degrading of resources (or the species that provide them) and, of course, being treated as a resource yourself. Happiness, as experienced by us and possibly other species, is a consequence of the degree that an individual's environment is optimally suited to maximize personal longevity and propagation of the individual's unique characteristics, and increasing it means using as many resources as possible.

The second story begins with two people, each using the minimum amount of basic resources (such as nutritional food, water, and breathable air) needed to live long enough to produce two more people and keep them alive long enough to survive on their own. Those resources are provided by a core set of other species ("supporters") which are doing the same thing and consuming resources supplied by another set of species ("producers"). For the system to last a long time, the supporters and producers must be allowed to reproduce so that their populations remain at least constant, otherwise the amount of resources drops, as do the populations of the creatures that depend on them – especially us.

Consuming the minimum amount of basic resources corresponds to a minimum level of happiness and lifespan, since none is left over for significantly altering an individual's environment beyond providing basic needs. The creation of physical and social technology (such as economics), especially since the beginning of civilization, has enabled the use of more resources as well as other types of resources besides the basic ones. This has translated into increasing happiness, longer lifespans (due to better health care, protection from predators, and a more reliable food supply). It has also supported larger populations, whose labor and ingenuity (higher probability of smarter and more capable people being born) has reinforced technology creation and use.

While we've so far protected the species that provide basic resources, we've consumed more than what other species produce, and have been consuming members of those species themselves. This consumption has included conversion of source material and energy into forms ("waste") that cannot be recycled by other species in a timeframe useful to humans, and may be harmful to them, even to the point of killing them off.

This brings us to the most important aspect of the second story. Humanity is now on the verge of consuming the producers that keep the supporters alive. Keep in mind that only the basic resources keep us alive and healthy; the other resources increase the quality and length of individual lives, and they enable growth in population by getting access to more resources. What will happen next?

In the first story, humanity is forced to retreat to a lower-consumption "world" which allows other species to grow back partially, thus providing resources for more people. We try to occupy this new world and then do the same thing again, resulting in oscillations in population ("popscillations") with a downward trend to a new value dependent on how much the species can bounce back before we overwhelm them again. If, with the second story, historical population and consumption trends are projected forward in time, humanity consumes some of the producers and stops when after our population drops in response to a shortage in basic resources. Then, after some settling, population and consumption both drop to much lower levels, potentially zero.

My new insight came from trying to understand that last drop, which at best seemed like radical overcompensation. After examining my underlying assumptions and being drawn back to the logic of the first story, I realized that humanity must be seeking a particular goal, manifested as reaching a limit in both population and consumption. Historical data showed that the best candidate was a condition where all that remains in the world is us, what we're consuming, and the supporter species. In short, we don't recognize the value of keeping producers around. Incorporating this into the story resulted in popscillation behavior like that in the first story: population drops in response to lack of basic resources, the species providing those resources partially recover, and the cycle starts over and over again, with an overall downward trend in our population. In this case, continuously increasing individual consumption repeatedly causes attempted overshoot of resources that drives down population in response.

As with someone who is banging his head against a wall harder and harder in the hope that it will move out of the way, avoiding further injury is best achieved by stopping the banging. If we're smarter, we'll avoid hitting the wall the first time (immediately stop population and consumption growth). Following this analogy, if the wall starts to move toward us, which is a conceivable consequence of climate change as species start to die off without our help, we should move backward (reduce our consumption) at least as fast as it is moving toward us. If we're lucky, and emphasize reduction of our greenhouse gas waste, the "wall" may slow down or stop before we are forced to reduce our population.

Impacts

My latest simulation of the future, which integrates personal priority-setting like that discussed in "Groups, Goals, and Actions" with the potential futures described in "Shutdown Scenarios," indicates that the best way to reduce major casualties over the next few years is to have everyone in the world immediately stop increasing both population and consumption of ecological resources (ecological footprint).

The urgency is a consequence of the possibility that humanity will breach a critical environmental limit in less than a year, killing off species needed to sustain those species we directly depend upon for our own survival. With global warming getting worse and threatening to push us over the limit anyway, we need to also work on decreasing our footprint with an emphasis on greenhouse gas emissions. This is the equivalent of slamming on a car's brakes before it flies into a ditch, and then backing up to escape collapse of the eroding ground under it.

Changes to personal behavior have an effect on the global whole that is inversely proportional to the size of the population and therefore extremely small (currently one in 7.26 billion). The best way to have a significant effect is to therefore convince many other people to make the same changes. For the expected ("combined case") scenario, I estimate that about nine times as many people can be saved as are convinced per year to stop growth in population and consumption, with the potential for billions of lives to be saved over the next 16 years.

In the worst case, higher population growth is projected before we make changes, and this results in higher speed toward the limit. To avoid hitting the limit and to minimize casualties we would have to now be decreasing our personal consumption by twice the rate we increased it last year, and stop at no more than 88% (and no less than 60%) of the current global average by the end of the century. Ideally, we should be following this approach anyway, following the sound advice of preparing for the worst case and hoping for the best case.

That "best case" is not, of course, my best case – it is the "limitless case" that seems to be the main planning scenario for the world. For that, there is no need to consider changing anyone's way of life, except to convince them to help increase our own happiness, population, and longevity. Given that our influence over our lives and those of our friends and family is much greater than any influence we might have over the rest of the population, it makes sense under this scenario to focus only on these groups. Doing so inevitably results in more consumption and a growing population, which a lack of limits allows so long as the corresponding complexity can be managed.

If I am wrong about the nearby limit my models indicate we are about to hit, there is another limit behind that: the effective depopulation of other species that includes those we directly depend upon. If we can proceed along the trajectory of the limitless case, I estimate we will hit that final limit by 2029 with a population of 8.5 billion people. If growth continues after that, then we are indeed on a world without limits, and I will stand corrected. There is, however, the very real threat of climate change that is expected by scientists to get much worse in the near future, as well as verifiable increases in pollution and species extinction that are a source of justifiable worry for the foreseeable future. 

We already know, or should know, that as biological entities our fates are intricately tied to the fates of our fellow creatures, and that we are collectively responsible for their fates taking a catastrophic turn for the worst. If our species follows them, then our personal and familial priorities will be forced to include the "others," and it may be too late to stop the worst from happening to us.