How Many Earths Would It Take For Everyone To Live Your Lifestyle?

How Many Earths Would It Take For Everyone To Live Your Lifestyle? May 1, 2018

The number of human beings on this planet has septupled (increased sevenfold) in a mere two centuries, from approximately 1 billion people alive in 1800 to more than 7.6 billion people today. Although there are indications that world population may peak at approximately 10 billion, should we accept 10 billion people as the “new normal?”

We also need to pay attention not only to the number of people alive at any given time, but also to related demographic trends. For instance, we have passed the midpoint of three significant shifts that have never previously been the case in the history of humankind if projected trends continue:

  1. Before 2000, young people always outnumbered old people. From 2000 forward, old people will outnumber young people. [To oversimplify, part of what this statistic is tracking is the likelihood that “All persons under 15 and those 65 or older are likely to be in some sense dependent on the population in the working ages of 15-64.”]
  2. Until approximately 2007, rural people always outnumbered urban people. From 2008, forward, urban people will outnumber rural people.
  3. From 2003 on, the median woman worldwide had, and will continue to have, too few or just enough children during her lifetime to replace herself and the father in the following generation. (Mayhew 217).

These are among the important trends to keep in mind as we seek to “build the world we dream about” with peace, liberty, and justice–not merely for some–but for all.

To help create a more sustainable world, another trend that I hope increasing numbers of people will help popularize is the need for a triple bottom line” that accounts for people, planet and profitnot merely profit alone. Two of my other recent posts (about the rise of robots and the need for human rights) have emphasized the ways human labor is exploited for the sake of corporate profits. But the recent celebration of Earth Day, isa reminder that it is also only fair that we consider the related importance of the environment in that triple formulation of people, planet, and profit.

Whenever I reflect on the relationship of people and planet, I’m often reminded of a New Yorker cartoon published about a decade ago. It shows a view from space with  an anthropomorphized Earth (depicted as having a face — two eyes, a nose, and mouth — looking up at another anthropomorphized planet Saturn (whose ring has been adjusted to have a head-mirror as doctors sometimes wear). The caption has Dr. Saturn diagnosing the problem of the ailing patient Earth: “I’m afraid you have humans.”

This cartoon satire visualizes a warning first made years ago by the late Julian Huxley (1887 – 1975), a British evolutionary biologist, who said that humanity: “will turn into the cancer of the planet.” That is a harsh evaluation, but consider the upward sloping line of “population size” in this graph. To Dr. Huxley, the rapid increase in human population looks like metastasizing cells threatening to overwhelm a vulnerable host— in this case the planet on which we find ourselves (Connelly 201).  

So I would invite you to consider that, as important as each part of the triple bottom line is, none are singularly important. More humans without end is not an unalloyed good—any more than the planet alone without humans, or profit alone for only a few wealthy elites. Now, in raising the topic of world population, I realize I’m steering into dangerous territory that is littered with the historic landmines of colonialism, eugenics, racism, and more. And I certainly agree that any proposal regarding human population must account for those deeply misguided tragedies of the past (Connelly 48, 50). With that in mind, I ask that you stick with me to let me get a few more points on the table.  

For instance, allow me to clarify that when I say, “More humans without end is not an unalloyed good,” I am primarily responding to a theologically conservative worldview that I was raised in and that continues to shape far too much political policy today. In contrast to a triple bottom line which calls us to account for the needs of people, planet, and profit—many conservative theologies say that:

  • More people is always better—and that it is a sin to use contraception designed to prevent a sacred human soul from being born (Connelly 50, 365).
  • How we treat the planet doesn’t matter because Jesus is coming back and God will magically create a “new heaven and a new Earth.”
  • [and] More profit is always better—indeed prosperity is a sign of divine blessing and poverty is due to a lack of faith.

For what it’s worth, my intention is not to be unduly flippant in that summary. I have heard these sentiments expressed many times—sometimes in those exact words.

The ethicist who I have found most helpful on this point is the Princeton University professor Peter Singer, who has written about Unsanctifying Human Life.” Part of what he means by this provocative formulation is that it is arguably no longer reasonable to maintain the ancient religious worldview that all human life is sacred and inviolable from womb to tomb without exception. (An extreme version of this ancient religious worldview has made it difficult to negotiate a reasonable public policy about reproductive justice and options for death with dignity.)

In contrast, here in the early twenty-first century, our invitation is to embrace the reality that we humans are not unique “children of God,” formed through a special act of creation 6,000 years ago—and rightful lords over both this planet and the other lifeforms on it. Instead, we live more than 150 years after Darwin’s discovery that we humans are not “a little lower than the angels,” but rather a “little higher than the apes.” We are the result of millions of years of evolution—and we are deeply interconnected with the other life forms and ecosystems of this planet.

As I have been researching this subject, the best contemporary book I have found so far is Fatal Misconception: The Struggle to Control World Population by Matthew Connelly, published in 2009 by Harvard University Press. And perhaps my most significant takeaway from his historical study is that attempts to curb world population have often been not only ineffective (even when the funding levels were high), but also racist, imperialist, and manipulative. In Connelly’s words, “The great tragedy of population control, the fatal misconception, was to think that one could know other people’s interests better than they knew it themselves (378).

On that point, from discussion and debates I have witnessed, one frequent confusion that sometimes keeps the topic of global population taboo is a category confusion of taking a problem personally that needs to be addressed on the institutional level of systems and structures.

The issue is orders of magnitude larger than whether any given person has no children—or twenty children. Systemic change will come, if at all, by addressing the larger systemic issues. And for those of us committed to reproductive justice, arguably the strongest and most ethical starting point is to move away from the paradigm of “population control” (which has a sordid history of racism, imperialism, and paternalism) to a paradigm of empowerment and equality—particularly for girls and women.

Systemic change should arguably include universal, worldwide access to comprehensive sexuality eduction, birth control, and child care—as well as equal educational and employment opportunities for girls and women. Indeed, if you consider the “population increment” bar graph segment of the chart linked to earlier, “The worldwide decline in fertility rates corresponds far more closely with the worldwide decline in illiteracy among women than with population control programs” (Connelly 375-6).

So that’s some of the good news: the world population is not predicted to keep increasing forever and we know how to further create positive change—educate, employ, and empower women. The annual rate of growth has peaked and is predicted to continue slowing down. The bad news is that interest in lowering world population has slowed along with it: “There has been no United Nations conference on population since the one in Cairo in 1994, and spending per capita on family planning programs has diminished considerably in most parts of the world—by over 50 percent in the decade 1996-2006,” which roughly coincides with the period when the rate-of-increase began to decline (Mayhew 214).

“The United Nations’ ‘median’ projection for global population now predicts that it will peak at around 10 billion” (Mayhew 3). But is it wise to accept 10 billion people in global population as the new normal? After all, a mere 150,000 years ago, there were only about one million humans alive on planet Earth. And whereas our semi-nomadic, hunter-gatherer ancestors had a relatively negligible impact on this planet, especially since the nineteenth-century Industrial Revolution, the high-impact, consumerist lifestyle of increasing numbers of humans is causing climate change at an unprecedented level.

Indeed, we may be hurtling us toward a potential sixth mass extinction here on Earth. Since we know there have already been five previous mass extinctions on this planet, we ignore the possibilities of a sixth one at our peril. Climate Change deniers may feel like only people and profit matter, but the contemporary environmental prophet Wendell Berry puts it this way: “Whether we and our politicians know it or not, Nature is party to all our deals and decisions, and she has more votes, a longer memory, and a sterner sense of justice than we do.” People and planet—we’re all in this together.

And as we consider how we humans might decrease our impact on this planet, there are a few additional factors to keep in mind. I should be sure, for example, to emphasize that the equation is not a simple division problem, as it is sometimes depicted. Our situation is not so simplistic as a numerator of finite planetary resources divided by a denominator of increasing numbers of humans. If it were that simple, then standards of living would decrease in direct proportion to increases in population. But techno-utopians—who think that technology will save us—remind us that over the past few centuries the “human capacity to innovate” has in many surprising ways been able to keep pace with the increasing number of new mouths to feed (Mayhew 205). Their hope is that technologies of the future will also save us from both poverty and climate change. (I’ve shared some details about those techno-utopia hope before in a previous post on The Earth Challenge.)

From the opposite perspective, techno-utopians sometimes fail to account for the ways that technological advances not only increase standards of living, but also have heavy impacts on our planet. Economists call this failure to weigh all implications an “eternality”—in this case, refusing to factor in impacts on the environment. And it is up to us to elect leaders with the courage to force corporations to internalize environmental impacts into their profits.

Here’s another way of making this point: not all 7.6 billion of us human beings alive today impact the planet at the same level. The issue is not only about the average birth rate of a given society, but also what size houses those children live in, whether they have air conditioning, whether they have a car, how often they fly in airplanes, etc. Each new person living a so-called “Western consumerist” lifestyle will have a much greater impact on the planet “than a billion more subsistence farmers” with multiple generations living together under one roof (Connelly 372).

Have you used the online “Ecological Footprint Calculator”? It is a fascinating—if sobering—interactive website created by a team of scientists which invites you to explore, “How many planet Earths would we need if everyone lived like you?” In the spirit of full disclosure, I’ve been a vegetarian (and occasional vegan) since 1996, I live in an 1,100 square foot row house, commute 7.5 miles to work, and I fly in an airplane at least a few hours a year. Along with a few other data points, that means that there would need to be at least 2 Earths for all 7.6 billion people to live my lifestyle.

For a few points of comparison, it would take:

  • 5 Earths for everyone to live the lifestyle of the average American
  • 3.2 Earths to support the lifestyle of the average German, and
  • and approximately 2 Earths to support the lifestyles of the average citizens of China, S. African, or Brazil.

These are important perspectives to wrestle with if we are to have any hope of achieving our goal of world community with peace, liberty, and justice—not merely for some—but for all.

For anyone curious, I did keep playing with my stats to see what it would take to get down to the “1 Earth” level. One way for me to get there would be to obtain at least 80% of my food locally, get rid of my car, and stop flying anywhere by airplane—most of which is not realistic given Frederick’s current logistics. And the overall challenge will increase with the projected 2.4 (or more!) billion additional people to come.

I don’t want to be unduly harsh on our species. From one perspective, we humans are amazing: we are the only products of the evolutionary process yet who have evolved the capacity of becoming aware of the evolutionary process itself! And our strong evolutionary impulse to reproduce is one reason why any of us are here at all. It is why our species has survived. But for a confluence of reasons—such as the domestication of fire and the increasingly-sophisticated communication potential of human language—we homo sapiens jumped to the top of the food chain with shocking speed—at least from the perspective of evolution.

Although we still must contend with factors such as war, disease, and natural disasters, it is also true that our species has, for a while now, been multiplying rapidly without any external predators to thin our herd (so to speak) and keep the ecosystem in balance—although that is part of what climate change is ultimately threatening to do.

But for quite a while now, people and profit have been rocketing upward, while attempted to count most of the impact on the planet as an externality. May we each do our part individually and collectively—within our spheres of influence—to co-create a sustainable future not only for all human beings alive today and future generations to come, but also for the multitudes of astounding life on this breathtakingly-beautiful planet we call home.

The Rev. Dr. Carl Gregg is a certified spiritual director, a D.Min. graduate of San Francisco Theological Seminary, and the minister of the Unitarian Universalist Congregation of Frederick, Maryland. Follow him on Facebook ( and Twitter (@carlgregg).

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