The Long View of Demographics
I am optimistic about humankind's ability to reach a sustainable balance with other life on earth, in part because the number of humans on earth will soon start to decrease. This doesn't mean that I think we should ignore our environmental problem—just the opposite: I think we should fight hard now with the confidence that we can win a complete and lasting victory.
We are so accustomed to watching the explosion of human growth and development that it is easy to imagine that this is normal. It is not. We are the first generation in history that has watched the human population double in our own lifetime, and no future generation is likely to see it again. All of those blights of growth that we have come to accept—crowded cites, jammed roads, expanding suburbs, fish-depleted oceans, and tree-stripped forests—are all symptoms of a one-of-a-kind surge in human expansion. Soon they will be just memories.
There are currently over six billion people in the world. There will probably never be more than ten. Population forecasts vary, but they all agree that human population growth is slowing. As people become more prosperous, they have smaller families. In every country where women are allowed free access to education and health care, rates of population growth are going down. Sometimes the trends are hidden by the delays of demographics, but the real population growth rates are already negative in Europe, China, and, if we subtract immigration, in the United States. The total human population is still growing, but not as fast as it once was. Assuming that these trends continue, the total population of the world will be shrinking well before end of this century.
This long view of demographics allows me to be optimistic even though almost every other measure of environmental health is deteriorating. We are suffering from our binge of growth, and the parts of our world that are the last to binge are suffering the most. The binge is not just in size of population, but also in the level of consumption. Yet, here too there is reason for optimism. We are so wasteful in our use of resources that there are huge opportunities for improvement. With more efficient technologies, our fundamental requirements for food, materials, and energy should be well within the carrying capacity of our planet. We should be able to support the peak of human population at a higher standard of living than the richest nations have today.
There is no doubt that the environmental challenges of the next decades are daunting, and they will require all the power of human striving and creativity to overcome them. Yet, I have no doubt that we will succeed. Innovation, good will, and determined effort will be enough to handle the next few billion people. Then as populations shrink, demands on resources will be reduced. Nature will begin to repair itself, reclaiming what we have so hastily taken. I hope we manage to keep the gorillas, elephants and rhinoceroses alive. By the end of the century, they will have room to roam.