As a former emergency room physician, how could I resist an invitation to review a book with "fractured" in the title? When I served as chief of the medical staff and director of emergency services, my job was to put people back together. But after years of practicing medicine, I felt like I was straightening deck chairs on the Titanic while the whole ship was going down. My interaction with 30,000 patients supplied ample evidence of a world made toxic by the stress of too much—too much soot in the air causing asthma attacks to escalate; too many chemicals in the environment, doubling our cancer rates; too many people on the planet living unsustainable, stress-laden lives. So I quit my job and started writing, preaching, and speaking full-time about caring for the created earth, based on my faith as an evangelical Christian.

Perhaps the most controversial issue that I talk about is population. Moral, intelligent, well-intentioned people hold sharply conflicting views on the population issue—an issue that is at the very crux of our environmental crisis. That is why the chapter on population in Allan Carlson's book Fractured Generations, though faulty in its conclusions, strikes me as worthy of discussion.

Fractured Generations is a book devoted to family policy issues. Carlson limits himself to one major issue per chapter, and ends each discussion with a list of public policy suggestions. I find myself agreeing with much of the reasoning in this well-researched book. My major source of disagreement with Carlson lies in Chapter 2, "Recrafting American Population Policy for a Depopulating World." Carlson tells us that many Western countries have either a nearly flat or slightly negative level of population growth, and that the United States, though still growing, may soon suffer the same future. He warns of a coming "surfeit of retirees" and an aging workforce that cannot compete on an international level.

In medical school, we were required to take eight semesters of statistics courses. Here's one statistic that no one argues with: the population of the United States has just reached the 300 million mark. At our present rate of growth, our population will reach 600 million in seventy years and one billion in a hundred years. And yet Carlson asserts that immediate policy steps must be taken to promote "greater fecundity" because "the demographic problem facing the twenty-first century is depopulation, not overpopulation."

Even if we were in danger of "depopulating," I disagree with Carlson's economic conclusions. He creates a false dichotomy when he implies that a sub-replacement rate of population growth will lead to dire monetary problems. If it's the workforce he's worried about, then all we have to do is open our borders. Countries that once depended on immigration for economic growth have slammed shut their doors. The rest of the world has more than enough people to meet the labor requirements of Western nations.

Indeed, the carrying capacity of the earth is a global issue, not a national one. If the children born between 2000 and 2005 were gathered on one island, that island would immediately be named the third most populous country in the world. On the flip side, not one island or acre of land has or can be added to this planet.

As I travel to speak with audiences about faith and the environment, I can see for myself the effects of population growth. In my lifetime, the world's population has doubled. The fields behind my boyhood home have sprouted "Woodfield Estates." Two-lane country roads are now six-lane highways. The streets of every major suburb are lined with cloned mega-box stores and chain-linked restaurants. Cities everywhere are becoming progressively more congested. This holds true around the globe.

When there is a problem I feel compelled to examine, I turn to the Bible for answers. The Bible devotes an entire book to census issues. In the book of Numbers, Moses records a census of the Hebrew population. Two thousand years elapsed between the time of Abraham and Jesus. During that time, the population grew steadily. If the human population continued to increase at the rate it did then, our current global census would be one billion. Instead, we have 6.5 billion.

What happened? The rate of population growth has changed because we—particularly those of us in the field of medicine—have fiddled with the limits imposed on us by nature. We have prolonged life, thus prolonging the length of each generation. By making three and four generations overlap, we have increased the total population of the earth.

One way of visualizing the rate of population growth is to take all of mankind's history and place it on a 12-month "Big Calendar of History." January 1 stands for the year 8000 BC. Each "day" represents twenty-seven years. December 31 on the Big Calendar of History represents ad 2000. Some important "days" are circled. In July, people start writing, building libraries, and using iron tools. In September, Christ lives, dies, and is resurrected. December 24 is a big day. By now 98 percent of all human history has passed. On this day, the Census Bureau throws a party. Mankind has reached the one billion mark. On the 29th of December, we reach two billion. We add another billion on the 30th, and during the 31st we add a billion in the morning, another billion in the afternoon, and another billion before midnight.

If we continue at our current growth rate, placing a check on the calendar each time we add a billion more to the census, January of the next "Big Calendar Year" will have sixty million check marks. This means that there will be sixty million billion people on the earth by the month's end, or ten people for every square foot of earth.

According to Carlson, the real reason for smaller families in Western countries is the rejection of Christian values. In fact, Carlson goes on to claim that religion is the number-one factor in determining birth rates, since religious people will, he assumes, desire large families and eschew the use of contraception. And Carlson is right when he says that people are having fewer children for selfish reasons. Declining birth rates are, in large part, the result of people turning away from Christian virtues like sacrifice, long-term commitment, altruism, and responsibility.

He is wrong, however, in his implicit assumption that everyone who had large families in the past was doing so out of obedience to Christian teaching. Human nature hasn't changed. Advances in medicine have simply given people new means of exercising their selfishness—or altruism—through contraception.

Is the use of contraception against Christian teaching? I have heard many versions of this argument, but they all boil down to the same thing: Contraception is against God's law, since it interferes with the created purpose of sexual intercourse. In short, contraception is unnatural.

I agree that contraception runs counter to "nature," and that science, by enabling people to engage in sex without the possibility of pregnancy, has altered the natural constraints within which previous generations of humanity have lived and died. But then, if we're being fair about this, science has also provided us with a number of decidedly "unnatural" ways to cheat death and prolong life. Indeed, our natural birth rate would not be a problem were it not for our current "unnatural" death rate. Why should we as Christians choose to accept what medicine can do to prolong life but abhor what can be done to prevent conception?

Throughout the chapter, Carlson seems intent on proving that underpopulation is real, and that overpopulation is a lie invented by social engineers to advance their agenda. The implication is that the concepts are mutually exclusive: either underpopulation is happening and overpopulation is a myth, or vice-versa. If we're just looking at the words themselves, this certainly seems to make sense. However, a little examination of what we actually mean when we say "overpopulation" and "underpopulation" reveals that the two terms inhabit different realms.

Overpopulation occurs when the human population exceeds the resources necessary for each person to have a good life. Underpopulation, in Carlson's terms, occurs when a country's population becomes too small for that country to maintain its economy in its current form. Underpopulation is an economic problem for specific countries. Overpopulation is a problem for the whole human race—a global issue.

Many of Carlson's claims regarding underpopulation are correct. There are a number of countries in the world—including virtually all of Europe, as well as Russia and Japan—that do not have a fertility rate necessary to sustain their current populations. And it is true that this may cause some short-term economic instability. But on a global scale, the problem isn't underpopulation, it's overpopulation. As noted earlier, any of the countries that have a static or shrinking population need only open their borders to immigration if they want to grow their population. There is no global shortage of people.

There is, however, a global shortage of the things necessary for each and every person on the planet to live a good life. When I say "good life," I don't mean a life lived according to the current North American standard; I mean a life that is good in the way that God intended it to be. Many of us go about our daily lives without once seeing God's creation unmarred by human hands. A growing global population will mean more human destruction of creation.

From an economic standpoint, there are ample resources to support a growing global population. But from an environmental standpoint, there are too many people consuming too much of the planet's resources. I don't want my grandchildren to live in Tokyo-style apartments in cities that cover thousands of square miles.

There can be little doubt that our environment is already suffering terribly from the selfish choices of humankind—indeed, from our lack of commitment, altruism, sacrifice, and responsibility. The lifestyle of the richest people on the planet—Westerners, mostly, though they have a growing number of counterparts elsewhere—is environmentally unsustainable. We already produce more waste, both in terms of landfill mass and in terms of chemicals, than we know how to deal with. More human beings and an ever-improving planetary economy will only exacerbate these problems.

As Carlson says, it all comes down to Christian virtue. Should I choose to have a large family and add even more people to a crowded planet? The Population Resource Board estimates that more that 106 billion human beings have been born since God issued the commandment to "be fruitful and multiply." I think that we can safely count "be fruitful and multiply" among the few divine commands that we have fulfilled. But we must not forget that this commandment applies to every one of God's creatures, not humans to the exclusion of all else. We are to be good stewards, not exterminators.

God has also given us another commandment—we are to love our neighbors as we love ourselves. I agree with Carlson that large families are preferable for a number of moral and economic, not to mention personal, reasons, but I believe that the Golden Rule trumps all other considerations. The suffering and the terrible quality of life that result from unchecked global population growth is more important than my desire for a large family, or my country's continued economic growth.

In my years as an emergency room physician, I saw thousands of people suffering from humanity's irresponsible treatment of the environment. How many more thousands of children must die from asthma before we recognize that air pollution is a killer? How many more million-dollar cancer centers do we need to build before we understand that prevention, not "running for the cure," is the answer?

The human race has a lot of progress to make before we can be considered good stewards of God's creation. I can all too easily imagine the catastrophic destruction that would result if every one of the 6.5 billion people on earth began to live like most Americans. My prayer is that these disasters will stay imaginary, and that my children and grandchildren will live in a world where every living person can drink clean water, breathe fresh air, and walk through unblemished forests.

My prayer is that God will act on the hearts of his people and help them to see that sacrifice is required if we are to live according to his plan. We can't keep using coal and gasoline at the current rate, or treating God's creation like a toxic waste dump. If we are serious about loving our neighbors, you and I cannot keep behaving much of the time as though we were the only people on the planet.

J. Matthew Sleeth is the author of Serve God, Save the Planet: A Christian Call to Action (Chelsea Green), coming in April in paperback from Zondervan.

Copyright © 2007 by the author or Christianity Today/Books & Culture magazine.
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