Many countries have been transformed in the last century by a sweeping demographic change, which shows no signs of diminishing in pace. Around the globe, fertility rates have fallen precipitously, family sizes have contracted, and populations have stabilized or contracted. We are still coming to terms with the many ramifications of that change, which echo through economic, social, political, and cultural life. But for all the discussions of these issues, all the projections of what it will be like living in a low-fertility world, one critical area remains largely neglected, and that is religion and religious behavior.
Rarely remarked even by expert observers, a direct relationship exists between the fertility rates of a community—the number of children that a typical woman bears during her lifetime—and that society’s degree of religious fervor and commitment. High-fertility societies, like most of contemporary Africa, tend to be fervent, devout, and religiously enthusiastic. Conversely, the lower the fertility rate, and the smaller the family size, the greater the tendency to detach from organized or institutional religion. Fertility rates provide an effective gauge for religious behavior and commitment, and rapid changes should serve as an alarm bell about incipient secularization and the decline of institutional religion. As I explain in Fertility and Faith, the term secularization oversimplifies the process substantially, but we may let that stand presently.
Of itself, such an idea is not new, and it has been explored to some degree as a causal factor in the dramatic decline of institutional faith in contemporary Western Europe. Recent projections, though, show that European-style rapid declines in fertility are now affecting much of the globe, and that those trends will become ever more marked over the coming decades. That is true whether we look at East Asia or Latin America, or at many Islamic nations. We would thus expect the religious character of those areas to alter—whether that means the decline and contraction of traditional structures, as in Europe itself, or some parallel development in tune with the distinctive traditions of other world faiths. Not just within the Christian world, contemporary religion is incomprehensible without appreciating that demographic dimension—of the shifting makeup and composition of populations.
In recent years, news media have regularly reported the sharp drop in fertility rates within the United States, a drop to levels that are now below those of Scandinavia. That story receives wide coverage, but largely lacking are the religious implications. A great deal of precedent suggests that such a change at long last heralds in this country the kind of secular drift (of secularization) that we associate with Western Europe. If so, the fertility drop is one of the most significant and newsworthy developments in modern American religion.
These bald statements about the relationship between fertility and religious behavior raise critical questions of interpretation. Merely to speak of a correlation between two phenomena says nothing necessarily about causation, but the fact of that linkage offers a valuable interpretive tool, which does have predictive value. If we look at the fertility rate of any society over the past few decades, we can form some likely hypotheses concerning that society and make predictions about how it will develop in the near future. We can make plausible statements about general social conditions—about the status of women or attitudes to family and to specific issues such as homosexuality—but we can also discuss religious conditions, concerning the state of organized religion in that society, or the status of clergy and religious professionals. Our deductions will not be infallible, and some exceptional societies demand detailed analysis and discussion, but in the great majority of cases, our assertions will prove broadly correct. In studying religious developments, demographic change is a bellwether statistic. To that extent God is (and always has been) in the numbers. Or, to adapt the celebrated maxim of Auguste Comte, in the realm of religion, demography is indeed destiny.
A world with the very low fertility rates that we are now observing is almost historically unprecedented—not wholly, but earlier examples are few. But although this is uncharted territory, we can reasonably project that such a low-fertility world will offer a deeply inhospitable environment for institutional religion and for many traditional approaches to religion itself. That does not of itself supply any kind of death warrant for the great religions, either in Europe or beyond, or for supernatural faith as such. Rather, in order to accommodate to new social trends, religions have to evolve new means of presenting their views, to address and accommodate societies where large families with abundant children are no longer the norm and where concepts of “family” are in flux. Of necessity, and in many different ways, those institutions will develop different emphases concerning morality and sexuality, gender and family, and also about the relative roles of clergy and laity in the institutional structures of a given faith. Demographic change is creating wholly new social and religious conditions. Institutions or faiths that hope to succeed and survive have no option but to take account of them and to adapt, accordingly.
Central to these changes is the question of fertility, a factor that can be measured in different ways. The General Fertility Rate (GFR) counts the number of live births per thousand women of reproductive age in a population each year. That reproductive age is defined as 15–44 years (or sometimes 15–49). In the contemporary United States, the GFR is about sixty births per thousand women aged 15 to 44—which is significantly down from what it was half a century ago. Much more commonly cited for international comparisons is the Total Fertility Rate (TFR), which is what I will chiefly be using here. The TFR measures the average number of children who would be born to a woman over her lifetime, assuming that she survives to the end of her reproductive life. To take some examples, France’s TFR is presently 2.06, while Egypt’s is 3.5. In West Africa, the figure for Burkina Faso is 5.7.
At that point, an obvious question should arise, namely how do we actually know how a woman’s record of childbearing at the present day can be used to predict her behavior over the whole span of her fertile years? The answer is that we do not know this exactly, but we can make projections with fair confidence. Theoretically, if we want to know about the lifetime fertility of women who are sexually active today, the only way to be certain is to wait until after they have finished their childbearing years, which might mean in twenty years’ time. But because fertility issues are so significant for the present day, we have to use some method to obtain a snapshot of behavior at any given time. Demographers thus take the number of women who bore a child in the previous year, then distribute the proportion of women according to their age. Based on what we know from that society, we can then make plausible predictions about those women over their life span and the number of children they will bear in all. The TFR is thus a synthetic figure. Like many social statistics, it involves a measure of extrapolation and projection, and there will be errors, particularly if a large cohort of women suddenly changes its behavior—for instance, to having children significantly earlier or later in life. This can produce misleading impressions of a baby boom, or bust. Generally, the TFR is an excellent guide to trends, and it offers a solid basis for international comparisons.
The Great Change
By itself, the fertility rate does not determine a country’s population, but it does have vital consequences, both in terms of the overall size of the population and (scarcely less important) its age distribution. If that TFR figure for a particular country is around 2.1 children per woman (roughly the present French situation), then the population will remain broadly stable, and that level is termed replacement rate. If the rate is much higher than that, say 4 or 5 per woman, then we will see an expanding population with many young people and young adults, with all the restlessness and turbulence that suggests. A fertility rate below 2.1—what we call sub-replacement—results in a contracting population and an aging society.
The contrast might be illustrated by taking two countries that stand at opposite ends of the spectrum of behavior and that offer wildly different models of possible demographic worlds. In contemporary Germany, which has a subreplacement TFR of 1.6, the median age of the population is 47.4. In central Africa, Uganda’s TFR is 5.8, and the median age is 15.9. Uganda has an extremely young population, with 48 percent of the people aged 14 or younger; the comparable figure for Germany is under 13 percent. One particular number that social scientists pay attention to is the proportion of the population who are teenagers or young adults, aged between 15 and 24—a stage of life often associated with unrest and, sometimes, violence. When that figure for any given society is much over 15 percent or so, demographers speak of a youth bulge and expect that fact to be manifested in various forms of conflict, instability, or economic strains.
The Ugandan figure is 21 percent, compared to below 10 percent in Germany. At the other end of the scale, 22 percent of Germans are aged over 65, as against 2 percent in Uganda. However crude the raw numbers, they suggest a great deal about the respective societies, not least about the demands on government and the relative importance of one’s family in supplying essential needs. These are very different social worlds. For some decades, demographers have explored these divergent models as ideal types, respectively named Fertilia and Sterilia; but real examples are not hard to find.
Over the span of history, fertility rates can rise or fall, but in modern times—mainly since the 1960s—they have fallen noticeably. In this regard, the present German situation has become typical of much of the advanced world. When the fertility decline first attracted serious notice in the 1960s, the illustrations used to describe it were usually Scandinavian societies like Denmark, although later years have shown that these would not in fact be the most extreme examples of change. Denmark’s TFR fell from 2.67 in 1963 to just 1.38 by 1983, although it has now recovered to 1.71. Such an apparent rebound is a little misleading in that much of the growth is found among newer immigrant communities, while the fertility of oldstock residents continues to be very low. In the economically advanced nations of the Organisation for Economic Cooperation and Development (OECD), the average TFR is now 1.7, down from 2.7 in 1970.
Japan offers an extreme example of the process at work. Since 1960, Japan’s TFR fell from 2.0 to bottom out at 1.25 in 2005, before rebounding to its present rate of 1.4. Even with that limited recovery, such a rate betokens a dramatic rise in the country’s average age. The median age of Japan’s population is 47.7, the highest in the world with the exception of the tiny European principality of Monaco. By some estimates, the country’s population over the next thirty years could drop from its present 127 million to below 100 million. To put that in perspective, as recently as 2002, Japan and Nigeria both had a similar population size, of around 130 million. By 2050 Japanese numbers will have fallen to at most 100 million, while Nigeria’s will have ballooned to over 400 million.
Social scientists have long understood the demographic effects of industrialization and economic progress, which promote a shift away from high death rates and high fertility. As far back as 1929, the idea of such a demographic transition was formulated by American scholar Warren Thompson, and the theory has been substantially developed in later years. Today that demographic transition is one of the most commonly used concepts in the study of populations. Since the 1980s the fast-accelerating rate of change in family structures and sexual attitudes has led scholars to speak of a Second Demographic Transition, at least as dramatic as the first, and with consequences far beyond the old developed world. So standard has the concept become in recent years that it has acquired its own familiar acronym, SDT.
What was not immediately clear was how the economically advanced societies that pioneered the demographic transition stood in relation to the rest of the world, which remained far less developed. In the 1960s and 1970s, commentators were alarmed by the growing demographic gulf between low-and high-fertility societies—between richer and poorer parts of the world. Many warned of a population explosion, the seemingly uncontrollable rise in the populations of poor and (then) undeveloped nations like India, Mexico, or Uganda. Western stereotypes imagined those “Third World” nations in terms of teeming legions of starving children and famished cities, and the racist undertones of the analysis were often thinly disguised. In a notorious work of fantasy fiction, The Camp of the Saints (1973), Jean Raspail imagined those beggarly South Asian masses pouring west to swamp and conquer the white world in an apocalyptic act of judgment and vengeance. That book has subsequently become something like a sacred text for the racist Right and for anti-immigration campaigners. So evident was the threat to planetary security that when the Vatican pronounced against artificial contraception in 1968, liberals and secularists widely criticized the decision as something like an act of treason against the human race. In 1989 the United Nations instituted World Population Day to raise awareness of continuing population growth.
But the spread of low-fertility patterns worldwide makes such images now look almost ludicrously outdated. Since 1970 Mexico’s TFR has fallen from almost 7 children per woman to 2.2—in other words, to just above replacement. In the same years, Vietnam’s rate fell from 6.4 to 1.9, Indonesia’s from 5.4 to 2.3, and India’s from 5.5 to 2.3. South Korea’s fell quite spectacularly from 4.5 to just under 1.0, which is one of the lowest figures on the planet. The change is still more marked in some regions within countries. Around half the states of India presently have TFRs below replacement rate, and such populous and influential states as Punjab and West Bengal have fertility rates below Denmark’s.
Most observers think that these recent plunges will continue over the next decade or two, to spread something like what are presently German demographic conditions around much of the non-European world. To put all this in context, I have noted how nervously Europeans in the 1960s viewed the explosive fertility rates of many Asian countries. Today, however, those same so-called Third World countries have TFRs that are actually lower than the European nations did in that earlier era, often by a sizable margin. One problem for anyone seeking to write about this process is that in many countries, rates are falling so fast that it is difficult to keep up with the latest numbers.
Looking broadly at the continents of Africa, Asia, and Latin America, some regions do indeed still have very high fertility rates—Uganda and Burkina Faso are examples—but many others do not. Moreover, different areas vary enormously in their degree of prosperity and economic development. In demographic terms at least, the whole Third World notion is obsolete, and only somewhat more valuable is the less judgmental successor to that concept, the Global South.
The reasons for the fertility decline are complex and will only be sketched here. As we will see, changes in birth rates and mortality rates both play a role, especially rates of infant mortality, and the interactions between these various factors make it hard to determine an exact path of causation. Throughout these transformations, it is all but impossible to determine the relative role played by social and ideological factors: changes in society and the economy created new ideological attitudes, which in turn drove new social revolutions. Beyond the general levels of wealth in a given society, technology and medicine are both critical.
The most obvious change involves the status of women in any given society and the life chances available to them. So many of the changes that I will describe here form part of a global gender revolution, a move toward broad gender equity that constitutes a sweeping transformation of social attitudes and relationships. To appreciate this imagine a preindustrial or premodern society in which young women have few available opportunities in the form of higher education or a career. The prospect of early death also makes it imperative that women begin their reproductive life early, so that they can have a realistic prospect of seeing their children reach adulthood. They begin bearing children in their teens and might well bear six or eight over their life span. That is all the more probable if the technological and legal environment restricts ways of limiting fertility. In Western Europe or North America, that older pattern was revolutionized even before the twentieth century. Gender roles were further transformed by the growing availability of contraceptives that were both effective and easy to use and that gave women the decisive say in deploying them.
In the United States, the “Pill” was approved for contraceptive use in 1960, and thereafter it became widely popular around the world. Economics played its role, with the rapid growth of service sectors as the most developed societies moved toward a mature postindustrial economy. Opportunities for women’s employment grew dramatically, as did female participation in higher education. Time and again, we will encounter those three closely linked drivers of change: women’s education, women’s employment, and contraception.
With new aspirations and opportunities in life, with a new commitment to education and career, women determined to postpone childbearing until later in life or even to forego parenthood altogether. A woman who postpones childbearing until her mid-thirties or later is unlikely to begin a large family on anything like the older model. New social attitudes also meant declining disapproval of couples who chose to live together outside traditional structures of marriage and family, with or without children. For large sections of the population, founding a family and raising children ceased to be the central and defining goal of life, and were replaced by other concepts of personal and career fulfillment. The demographic revolution is above all a gender revolution. When scholars study the Second Demographic Transition in a particular region or nation, they measure crucial trends such as female participation in the labor force, rises in premarital cohabitation and the number of children born to cohabiting couples, and the postponement of both marriage and parenthood. Gradually such changes have spread beyond the traditionally developed world, to transform new lands, and they are continuing to do so.
Whatever their origins, those demographic changes have vast consequences. Just to take Japan as an example, that country’s workforce could by 2040 be 20 percent smaller than it is today, and a falling number of taxpayers will be available to support the needs of a fast-growing population of retired elderly people. An aging population and a scarcity of children echo through the whole economy. They determine how businesses market goods and services, how they build and furnish apartments or houses, how they organize public transportation. Demographic change correlates with shifts in mores and attitudes—although the direction of causation is open to discussion. A society that moves away from traditional views of the child-centered nuclear family is likely to be open to nontraditional views of sexual behavior and the rights of sexual minorities. Seemingly eternal and inevitable structures of family, gender, and sexuality are all in flux.
Each of these changes has its impact on religious structures and behavior, and migration offers one powerful example. When a society makes the decisive move to sub-replacement fertility, it faces pressing needs for labor, which is commonly imported from poorer high-fertility nations, often far afield. But despite its strictly economic motivations, that immigration cannot fail to have broad cultural effects. It often serves to spread particular forms of religion, by importing new faith traditions, or new denominations, into a society where they did not exist before. We naturally think of the new Islamic presence in post-1960s Europe, but new Christian communities have also established themselves across the continent. Less noticed than the European story, a similar process has brought sizable Christian populations into the Arab Gulf nations that not long since were almost monolithically Muslim. In all these cases, migrants often return to their home countries, whether temporarily or permanently, and they bring with them the religious ideas and attitudes of those wealthier and more advanced nations. That further accelerates the process of religious cross-pollination and of globalization. If we just consider migration alone, demographic change drives religious transformations.
But the demographic impact is much more extensive and more pervasive. In whatever era we are considering, the history of religion and religious change has to take account of issues of demography. Depending on its demographic character, a society might have a high or low birth rate; its members might expect a long or short lifespan; people might be prone to disease or unusually healthy. A society might be homogeneous in terms of race, ethnicity, and language or very diverse. Any or all of these issues have wider effects in terms of the stability of a particular society, the rate of social change, and the concentration of settlement and urbanization. Such factors can change over time, often quite swiftly. Whatever its exact demographic profile, those features have a profound effect on religion, in shaping the audiences that are available for particular messages and approaches. As many scholars have noted, religious behavior can usefully be explored through the analogy of a marketplace, in which suppliers and providers succeed or fail depending on how far they take account of shifting patterns of consumption and consumer tastes. This applies to the kind of religious faith that gains the most followers, the means by which it is practiced, and the most popular forms of religiosity and devotion.
A society with a great many teenagers and young adults—a youth bulge—offers particular opportunities to revivalist and evangelistic movements preaching a fiery, enthusiastic faith. An older, more stable society has quite different needs and interests. Cities, again, offer opportunities and challenges quite different from those of villages and small towns, and that is especially true when those cities are growing quickly. Changes in the role and autonomy of women offer particular challenges and opportunities for religious institutions. A substantial scientific literature now amply confirms that women are more religious than men, and that distinction holds good across societies, so that any loss of female adherents has a uniquely damaging effect on a church or institution. Wise religious organizations tailor their activities and rhetoric to the communities that they have to deal with, and if they do not do so effectively, they will lose influence to newer and more efficient rivals who have a better sense of audience and marketplace. Demographics shape religious life and behavior, and they always have.
In the modern context, we repeatedly find a potent correlation between fertility and faith, so that a list of the world’s nations by fertility rates will be very similar to a ranking of countries by their degree of religious belief and behavior. To say that Denmark (for example) is at once a low-fertility and a low-faith society is to make an interesting observation, just as it is to point out that Nigeria represents very high fertility, and intense faith, expressed in different traditions. But when such correlations occur frequently and examples accumulate, it is probable that we are dealing with a real relationship between the two elements.
A society that falls significantly below replacement rates is likely to face a steep decline in institutional religious forms, and often of religiosity more generally. As is well known, the low-fertility societies of Europe also rank at the bottom of any listing of countries in terms of religious commitment and belief. A change in one of those elements, demographic or religious, will be followed by a development in the other. Historically, the European shift toward very low fertility from the 1960s onward coincides exactly with the precipitous drop in religious behavior in those same years, and both patterns spread together to new regions of the continent. More recently we observe the twin shifts occurring in many different parts of the world, beyond Europe. The accumulation of evidence strongly suggests that demographic transitions also mark religious transformations—that fertility and faith travel together.
Causation and Correlation
Such a statement raises well-known questions about identifying the chain of causation, a problem familiar to anyone who ever took an introductory statistics class. If two trends follow each other closely on a graph, we can interpret their relationship in various ways. Perhaps trend A is influencing and driving trend B; or else B is influencing A; or else both A and B are both driven by another factor, C. Alternatively, perhaps the apparent linkage between A and B is coincidental, and there is no linkage whatever. That final explanation becomes ever less likely as we find more and more examples of the two trends running together, in multiple different settings and eras. That then leaves us with the three basic narratives about causation. In the contemporary context, we can see several possible reasons why lower fertility rates should be connected to declining religiosity. I discuss these factors at greater length in Fertility and Faith but will sketch them briefly here.
One path of explanation suggests that religiosity declines first, and that then leads to declining fertility and smaller families. As is commonly noted, larger families do tend to be more connected to religious institutions and more committed to religious practice. Perhaps conservative and traditionalist believers tend to be more family-oriented, more committed to continuity and posterity, and thus they have more children; or else people in large families tend to be more conservative, more vested in traditional religious faith. To take one example of many, one American study described the completed fertility of women in their forties in the period 2013–2015, and that was based on the actual number of children born in their lives, rather than any projections or estimates. The religious conclusion was clear.
The rate for fundamentalist Protestants was 2.6 children per woman, with Catholics at 2.2 and mainline Protestants at 2.0. Those of “no religion” had a rate of 1.5. Again, if this was one isolated example, it would be a suggestive tidbit, but it is not: such findings are commonplace (although in recent years, even these once solidly rooted assumptions might finally be changing). Indeed, the association between conservative or traditionalist religion and high fertility is often used to explain the relative success of conservative denominations in modern U.S. history, at the expense of liberal mainliners. What separates the winners and losers in the religious economy is not the soundness of their theology but their fertility rates. But now let us imagine conditions changing so that levels of religious belief decline and the number of people with no religion grows; then we would naturally expect a consequent fall in fertility.
Alternatively, we might suggest that fertility declines first and that this has its impact on religiosity. We note for example that smaller families reduce their ties to organized religious institutions, as there are simply fewer children to put through religious school and First Communion classes, or the equivalent training and socialization that exists in other religions. As religious ties diminish, ordinary people increasingly define their values in individualistic and secular terms, and are more willing to oppose churches or religious institutions on social and political issues of gender and morality. Even in once solidly Catholic countries, we see the advance of contraception, abortion, and same-sex marriage, and a precipitous decline in church attendance and participation. In many nations the decline in fertility correlates neatly to the fast-growing acceptance of the practice of same-sex marriage, which was a near-unthinkable concept just a few decades ago. Around the world we regularly see a dependable pattern: as fertility rates fall, so gay rights grow.
But it is scarcely necessary to determine an exact sequence of change, as the two factors, fertility and religiosity, work so closely together, and developments occur within a short time span. We might imagine a community that becomes increasingly detached from traditional religious-based concepts of gender roles. That reduces the ideological pressure to define one’s role in terms of family, parenthood, and posterity. As women become emancipated from familiar roles, they become more deeply involved in the workforce and do not have time to contemplate the large families of their mothers’ generation. That in turn reduces ties to religious institutions. A shift to lower fertility encourages declining religiosity, which in turn would discourage religious enthusiasm, and so on, in a kind of feedback loop. The two factors—family size and religiosity—work intimately together in ways that are difficult to disentangle. If the correlation between fertility and faith is strong and easily demonstrated, the precise nature of causation is not so clear, nor need it be.
As I have remarked, any discussion of fertility rates also has to take account of mortality. The fertility transition involves birth and death rates changing more or less simultaneously, with infant mortality an excellent gauge of the shift in process. Again, these trends are inextricable and interdependent, but they are also essential to understanding religious change. As advanced societies no longer live in the midst of death—at least, in the constant presence of visible and frequent death—so their attitudes to life and the afterlife are both in transition.
In Search of Security
Changes in both fertility and faith might be driven by an additional factor—the element C from my sketch above—which we can term a sense of existential security, both individual and collective. As societies become more advanced and economically sophisticated, ordinary people benefit from greater stability, improving medicine, and a better social safety net. Reinforcing and globalizing these trends are critical changes in technology, which open new employment opportunities and offer easy access to effective contraception. Among other things, this new world allows families to be more confident that children they have are likely to grow to healthy adulthood. Accordingly, they no longer face the need to have many children to contribute labor to subsistence economic activities and to support them in old age. Of themselves security and stability tend to reduce fertility.
At the same time, those same factors undermine many of the attractions of religion. Just to take one factor, a medically advanced society is much less likely to be afflicted by endemic diseases and ill health of the kind that so often inspires religions based on healing. In modern societies, such miracles become unnecessary and obsolete. This does not mean that healing churches or sects are unknown in advanced societies, but they occupy a far smaller part of the spectrum of religious behavior. Often, too, such modern healing movements focus not on obvious material complaints but on the healing of psychological conditions or personal failings. That move away from the healing role of religion is a historic shift. Indeed, in counting the key figures whose work massively reduced the appeal of religion, we should probably pay less attention to Marx, Freud, or Darwin than to Louis Pasteur, for his pioneer work in medical innovation and the germ theory.
Similarly, a state with a sophisticated social welfare system is far less troubled by extreme and widespread poverty or by life-threatening hunger. No longer do religious institutions occupy a key role as the faces of the charitable endeavors that keep people alive. Doctors, states, and social workers appropriate many of the functions long held to be the terrain reserved for clergy and holy people.
To appreciate the power of these security factors, we need only imagine a society where they are conspicuously absent, a society marked by pervasive poverty and deprivation, by widespread diseases and ill health, and by social turmoil. In such communities, economic structures offer little role for women beyond the most basic forms of physical labor, and they will bear and raise many children. As we will note in many cases in Africa and the Middle East, a very fertile society is likely to experience endemic conflict, partly because it is unable to cope with its cohort of young adults. The longer such conflicts last, the harder it is for that country to make the kind of economic progress that will provide jobs for women, and that in turn reinforces the patterns that produce and sustain high fertility. It is not hard to see how existential insecurity would be associated with high fertility and with high levels of faith.
The argument linking religion to security undoubtedly has much to recommend it, and I will often have occasion to return to these general themes. At the same time, we cannot simply draw a deterministic link between levels of prosperity and technological sophistication and the decline of religion. If that were true, then (for example) the United States would have led the way in secularization over the past century, rather than being long celebrated for its stubbornly high degree of faith and religious expression, not least in politics. That may well be changing in recent years, but even if it is, the long delay raises serious questions about any neat equations we might construct. So do other examples from different parts of the globe. Economic change always has to be considered in the context of cultural developments.
The consequences of the fertility/faith revolution are open to debate. At first sight so much about the lowfertility scenario is attractive, even utopian, and the spread of Western models worldwide could presage a global decline in extreme poverty and immiseration. Ideally we are imagining societies that are far more prosperous and healthier than any of their predecessors, more equal in terms of gender, more secular, and above all, more stable. We would generally see a diminution of factors making for aggression and violence, and for some traditional expressions of masculinity. Ideally too, a society with a dearth of young adults would likely be more careful about engaging in military conflicts, at least in ways that threatened mass casualties. Domestic political violence also becomes less likely when there are fewer young adults to fight for causes. An eventual lowering of population levels would reduce the strain on global resources and even limit damage to the climate. Taken together the scenario sounds like a real-world rendering of John Lennon’s song “Imagine,” with its total absence of any religious dimension: above us, only sky. Religious believers might even face the dilemma of whether the near extinction of their faiths is a reasonable price to pay for so much evident improvement in the living conditions of the hitherto impoverished. In fact, anyone who objected to such a scenario would face an obvious question: What do they not like about the new world, the peace, the health, or the prosperity?
But problems are also apparent, and it remains open to question just how long a sub-replacement-fertility society can remain economically viable. If commentators of the 1960s panicked about the thronging cohorts of children and young adults pouring forth from the Third World, modern-day observers are much more concerned about the menace to social services and care facilities posed by many millions of the old and very old, with all that implies for fiscal wellbeing. Such problems are already evident in Japan, as in much of Europe. Some writers have spoken of Europe’s demographic future as a “geriatric peace.” This is a highly ambiguous concept that at once points to the virtues of stability while warning of stagnation and weakness. For all its prosperity, all the measures of the health and longevity of its people—unimaginably high by the standard of previous generations—contemporary Western Europe still falls far short of a Utopia.
At the same time, rapid demographic change of the kind I am describing opens the way to multiple conflicts of varying degrees of severity, to tensions both domestic and international. The problem lies not in the fact of demographic change but in its patchy and sporadic nature. Differential rates of change can create profound imbalances and tensions, and even result in violence. A comment attributed to esteemed science fiction author William Gibson observes that “the future is already here. It’s just not very evenly distributed,” and that caveat applies strongly to demographic realities. If the great fertility shift will eventually transform the whole world, it has not done so yet. It would be convenient if all societies in the world shared identical demographic trends, but they do not. Besides the regions of declining fertility, many other parts of the world retain very high fertility patterns and the demographics we traditionally think of as Third World, as in Uganda. In the vast Democratic Republic of the Congo, the TFR today stands much where it did in 1960, at over 6 children per woman. Such societies are characterized by strong religiosity, sternly traditional gender roles, and (often) sharply defined concepts of masculinity and honor. Those societies also tend to be more turbulent and unstable, with weak states and high levels of violence. Although such countries will presumably pass through the demographic transition and fertility decline, it could be several decades before this happens.
Such international disparities would matter less in a world of poorer transportation and communication, lacking the globalization that is now so advanced. If Europe (say) has definitively made the transition to a new social and demographic world, then large portions of North Africa and the Near East have not. In terms of social realities, that is a world decades or centuries removed from modern Europe, but only a few hundred miles in geographical distance. People literally can walk and sail from Syria or Burkina Faso to Germany, and a great many have done just this in the refugee wave of recent years. Those refugees share demographic patterns, and the associated values, radically different from those of the host nations, and culture clashes are inevitable. Commonly, those differences take the form of religious identities and resentments.
Something like the European refugee crisis is an extreme event, but other less spectacular outbreaks can cause tensions between very different demographic worlds. In many countries the high fertility pattern and strong religiosity of new immigrant populations set them apart from old-stock communities. Disparities that emerge often take a mild form, but they can become severe. Differential fertility rates make existing conflicts over race, ethnicity, and identity still more acute, adding a poisonous new element of generational resentment. Nor is this a simple story of Muslims from an older demographic world confronting a socially advanced Christian or post-Christian Europe. In terms of demographic patterns and religious outlook, Global South Christians are in many ways more akin to their Muslim neighbors than their European coreligionists.
Also, demographic decline is by no means a straight-line uniform process, even within a single country, and it can affect communities to different degrees. Around the world many nations are divided between high (and low) fertility areas, with different communities having very disparate levels of access to wealth and education. Those distinctions might be geographical, dividing regions, or they might divide classes living in near physical proximity. Generally, the low-fertility communities tend to be wealthier and more economically developed, and more secular; their high-fertility compatriots are poorer and more religious. So stark are divisions between different communities as to make them appear almost like rival societies, if not competing nations. In recent years, populist and sometimes authoritarian regimes have emerged in various nations, basing their power in socially conservative regions, or populations marked by high fertility and high faith: Turkey and India are conspicuous examples.
The world will not, therefore, evolve neatly and homogeneously into an idyllic secular society of low fertility and low tension, but nor will it be partitioned neatly between high- and low-fertility societies, between old and new world orders. There will be constant adjustments and evolutions, as the shifting fault lines between societies and religious outlooks mark the borderlands of conflict. Aggression, violence, and tension are to be found in the essence of neither the old world nor the new, but along the constantly fluctuating boundaries between the two. Those boundaries divide continents, nations, and regions. When old and new social orders do come into conflict, their struggles are expressed in a common currency of very contemporary technologies and social media. The old world fights with very new weapons. In demographic and cultural terms, the world is anything but flat.
EDITORIAL NOTE: Excerpted from Fertility and Faith: The Demographic Revolution and the Transformation of World Religions. Copyright ©Baylor University Press, 2020. Reprinted by arrangement with Baylor University Press. ALL RIGHTS RESERVED.