DiscussionWhile a commitment to zero growth need not be based on a perception of the threat to the global environment unrestrained growth represents, it is probably through this concern that most people come to subscribe to the ethos of zero growth. To assess the seriousness of the various threats we face, I offer the following simple categorization. Additions to the threats or comments on their relative ranking are welcome.
(Human) Species-Threatening
OZONE DEPLETION - While many assume the risk arising from this well-documented phenomenon is no worse than a bad sunburn, who can say what the final consequences will be? Even if we stopped all chlorofluorocarbon (CFC) production today, the amounts we have already released into the atmosphere will continue to eat away at the ozone layer for decades to come.
DECLINING SPERM COUNT - Obviously, no sperm, no babies, no human beings. The count doesn't need to get anywhere near zero to put us on the endangered species list. The perplexing thing is nobody seems to know why the little swimmers are disappearing.
NUCLEAR WAR - This venerable threat remains with us and will until swords are beaten into plowshares or an even more diabolical form of mass annihilation is developed.
BIOTECHNOLOGY - In procedures reminiscent of fictional mad-scientist experiments, bio-engineers fiddle with the building blocks of life in hopes of creating better fruit, sheep, and - who knows - someday humans? Dr. Frankenstein must be rolling over in his grave contemplating what unexpected results might transpire, perhaps making humans as endangered a species as a flock of monarch butterflies in a field of genetically altered corn. Will man be the first species to create the agent of his own demise?
Catastrophic
GLOBAL WARMING - Though some might consider the inundation of all the world's great coastal cities a blessing of sorts, the adjustments required by this worrisome trend are likely to be massive and painful. But, we should survive as a species, as long as it doesn't get too hot and the factors causing the phenomenon don't destroy the atmosphere entirely.
RESOURCE EXHAUSTION - The realization that we live on a finite planet with many non-renewable resources is likely to hit hard in the first few decades of the new millennium, but perhaps our technological genius will make up for our limited capabilities at foresight. Oil heads the list of resources whose dwindling supply could touch off massive social dislocation, deprivation, and war.
OVERPOPULATION - This problem could well lead to human misery on a scale never before witnessed or even imagined, but it's primary impact is likely to be restricted to the Third World. Those in the richer, more population-stable parts of the world will not be unaffected, however, as political instability, immigration pressures, and travel hazards bring the tragedy home, causing more than just condescending hand-wringing and an occasional pang of guilt.
MICROBIAL RESISTANCE - The ability of those pesky microbes to mutate into forms resistant to our antibiotics has spawned a footrace between the scientists' attempts to develop antibiotics lethal to the new microbes and the microbes' will to survive. Which species will win this Darwinian struggle is as yet unclear, but should the microbes get the upperhand, it could mean illness and death on a scale not seen since the Middle Ages.
Unpleasant
DECLINING AGRICULTURAL OUPUT - As with overpopulation, this trend, resulting from soil degradation, urban sprawl, falling water tables, etc. if it occurs, will hit hardest in the poorer areas of the world. The decline will exascerbate the problem of overpopulation or perhaps solve it - through the unpleasant mechanism of mass starvation. How the well-fed rich of the world respond will be a test of our humanity.
POLLUTION - Future generations may never know how blue the sky once was or how majestic the view of distant mountains, that rivers once ran clean and teemed with fish, that forests were once dark and deep, not growth-stunted and diseased, or that societies were not always afflicted with cancer, respiratory disease, and congenital defects; but, hey, what they don't know won't hurt them. Encouragingly, many remedial steps have been taken to save our children from this fate, but, if growth continues to thwart our every effort, some of the individual contributors to the problem (acid rain, smog, toxic waste, pesticides, etc.) could move up the scale to catastrophic or even species-threatening.
SPECIES EXTINCTION - The world may be a poorer place because of the extinction of many of our fellow life-forms, but until we are down to a few dozen survivors it may not be of great consequence except to pharmaceutical companies, big game hunters, and butterfly collectors.