The word sustainability has almost lost all meaning in environmental discussions, as it has been applied to all manner of human activity. Many are inclined to drop this word and use others in their stead.
Resilience, sustainability, adaptability. I hesitate to throw away any words, as words have meaning and reducing our vocabulary creates a depauperate language.
The word "sustainable" is particularly difficult because it is used to opposite meanings in economics and biology. Sustainable in classical economics means: "making decisions and strategic investments to sustain the community over the long-term." In biological terms, sustainable means "making decisions and strategic investments that are not harmful to the environment or deplete natural resources, and thereby support long-term ecological balance."
The concept I'm searching for is a quality of human society that allows it to continue indefinitely into the future without reducing the carrying capacity of the biosphere that sustains it. This concept embraces sustainability, resilience and adaptability.
Adaptability is a particularly slippery concept, because humans do not adapt to the world in the biological sense that others species adapt through the process of biological evolution. Rather, humans actively adapt the environment to human needs and desires. We do not grow fur to live in northern latitudes, we take from natural resources to invent fitted clothing and insulated houses. We do not grow gills and flippers to fish in the sea, we invent boats and fishing tackle. We change our environment to suit our needs. We are an impatient species, with no time for mundane evolution to bring us into conformity with existing conditions.
What is needed rather than adaptability is forbearance, the quality that Scots call ”let-a-be,” that Taoists call "wu-wei," allowing the world to rise of itself, rather than to shape it into predetermined human patterns.
What would a "wu-wei" human economy look like? Such an economy would take no more resources than are naturally replenished, leaving sufficient resources to support all life. Wastes would not be produced in greater amounts than are naturally assimilated through existing geophysical processes. Food for humans would be grown within existing cycles of resource availability and biodiversity.
In short, human societies would exist in a dynamic equilibrium with all other species, subject to natural cycles of resource availability. Humans would a be a part of, not apart from, the non-human world.
Non-human species have lived this way all the time. Those that fouled their nests or outgrew their food supplies declined or went extinct (or adapted and flew away). The process continues today, with the addition that non-human species must now adapt to the human propensity to ignore evolution and demand dispensation from adaptation.
Human economies are created and maintained to suit human desires and needs. They are a mental constructs subject to human construction and modification. We "Homo sapiens" invented our way into the environmental mess that our economies have created. We have the capacity to invent our way back into a cooperative, co-evolutionary relationship with non-human species that will benefit all and ensure our species' place on this planet in the future.