At present, people in the U.S. and a number of other nations have made their decisions clear. They — we — believe in unsustainable living. We are going to continue to expand the population, and each new baby will follow in our practice of consuming and wasting more than the planet can handle over the long run.
Along with the obvious drawbacks of such a strategy, there is at least one positive implication of this approach. It seems that there are different ways to live unsustainably, and some are actually important to human life. For instance, on the side of excess consumption and waste, there are feasts and parties at which people eat and drink far more than they would normally, and those can be great experiences; there are rockets and race cars that burn way too much fuel on a per capita basis, but their consumption may be appropriate in light of their typically short and unusual performances.
Along with unsustainably excess consumption, there is also such a thing as unsustainably insufficient consumption, and these instances can be important too. For example, if people ever fly to Mars, they are going to have to take along most if not all of the things they will need, and the same has commonly been true for sailors, pioneers, and explorers. Indeed, every day, people run caloric deficits in their physical sports and labors. You really can’t live without going heavy at some times and light at others.
Unsustainable insufficiency is very common, and not entirely bad. You might spend hours, days, weeks, or even years in circumstances where you would be inclined to eat more, consume more, and waste more, but can’t quite manage it. Actually, that may be a fair description of how the vast majority of humans have always lived. Despite such limits, people have found ways, through the centuries, to experience some meaning and pleasure in life. Of course, the material deficits in their life experiences have also tended to be good news for the physical environment. Not getting everything you want means consuming and wasting less.
Leisure is an important kind of unsustainable insufficiency. As just noted, recreational activities often entail burning more calories than you happen to be consuming at the moment. You can’t keep that up forever, but it can be great while it lasts. Likewise for other forms of unsustainable insufficiency. In the case of unemployment, for example, there can be various detrimental physical and psychological consequences; but if you can manage those (through e.g., material help from a supportive society and mental adaptation to the opportunity to spend much more time with friends and on activities of personal interest), a shortage of employment can ironically open up leisure opportunities that are simply not available to people who do not suffer from such a deficit.
The point of these remarks is simply that unsustainability is not necessarily bad. Excess and inadequate consumption have their place, in the short term and sometimes also in the longer term. Along with its potential benefits to the environment, inadequate consumption can inspire ingenious ways to achieve more with limited resources — to experience as much happiness with four hours’ worth of daily income, perhaps, as other people experience with eight. Opportunities to experience more leisure may encourage efforts to get by with less, and to be as happy if not happier in the process.