Though many individuals and parishes within it may disagree, the hierarchy of the Catholic Church has long refused to admit the seriousness of the problem of overpopulation and has even, unfortunately, done much to obscure the issue. A good example is this statement from the Pontifical Council for the Family, dated February 27, 1998:

The impression left on the casual reader by these statements is that the population problem is illusory and that in many places we may soon be faced with the problem of not having enough people. Nothing in the broader context in which these statements occurs changes that impression; on the contrary; it is consistently maintained throughout the entire document.

According to the Pontifical Council, the idea of exponential population growth belongs to an "erroneous popular vocabulary." In a sense this is true; if you want to get very technical, population growth has not been a precisely exponential curve; but to a close approximation the curve is exponential. For hundreds of thousands of years, human population was well below one billion. It reached one billion only in 1850, two billion in 1930, three billion in 1960, four billion in 1976, 5 billion in 1990, and 6 billion in 1998.

The Pontifical council notes that since 1968 the rate of growth has declined, but fails to make two important points clear: (1) this decline in the growth rate is very slight, and (2) a decline in the growth rate is not a decline in growth; it merely means that the population is not growing quite as fast as it was—but the fact remains that it is still growing very rapidly—at about 1.8 percent per year. Even if this rate were to slow much more than it has, say to 1 percent per year (and there is no good reason to think that it will anytime soon)—population will continue to increase rapidly. At a one percent growth rate, which is much less than the current rate, population still doubles every seventy years.

Moreover the Pontifical Council’s statement that 51 nations are no longer able to replace their population is simply untrue. One of the fifty-one, for example, is the United States. The United States is not only able to replace its population; its population is in fact continuing to grow and will grow into the foreseeable future. The Pontifical Council bases its claim that the that the U.S. (and the other fifty countries) are unable to replace their populations on the fact that their birth rates are less than 2.1 children per women, which they consider to be the replacement rate. That replacement rate figure itself is questionable, but even if we grant it for the sake of argument, there are still three other errors in the Pontifical Council’s reasoning:

1. They ignore immigration. Population is replenished not only by births but by immigrants. The fifty-one nations mentioned by the council are mostly industrialized countries. And in fact population growth in industrialized nations is due largely to immigration from parts of the world in which the birth rate is much higher.
2. The Pontifical Council ignores increasing life spans. As life spans increase, generations increasingly overlap. This increases the population even if the birth rate stays exactly at replacement level. Life spans are increasing throughout much of the world.
3. Even if a nation’s birth rate is below 2.1 children per woman, that doesn’t mean that the nation is unable to achieve a higher birth rate, but only that it has not chosen to do so. If a higher birth rate were desired, it would no doubt be possible in any nation on Earth.