Some means of lowering birth rates have nothing to do with direct appeals to prospective parents. Around the world, birth rates drop quickly when women start to have more education and more opportunities outside the home. Women postpone childbearing until later because they have the option of establishing a career. They have fewer than the maximum number of children because there are other things they would like to do with their lives. Birth rates also drop when infant mortality rates go down, giving people the confidence to stop at two, instead of having more as an "insurance policy” against loss of their first children. Plus, birth control and abortion bring down the birth rate by enabling people to have better control over how many offspring they bring into the world. These sorts of mechanisms, not an ethics of reproduction, are the main drivers of population size.
If social messages also have some role to play, they are messages not so much about right and wrong but about social responsibility— that is, being aware of and concerned with the impact of one’s actions on matters of broad social concern. What counts as socially responsible is forever changing. Once bottled water seemed innocuous, but then environmentalists started telling us that the cost of all that plastic and transportation wasn’t worth it, considering our plentiful and clean water supply. Once flying to exotic locations seemed fine (if you could afford it), but then we started to be told about the greenhouse gases produced by airplanes. The messages we get about bottled water and travel are quite different from a black-and-white moral message. It’s not outright wrong to drink bottled water—it’s just something we should cut back on, if we can. We ought to think about travel and its environmental impact, but we’re not wrong to fly to Paris.
This isn’t just splitting hairs. Wrongs are not corrected by rights. If you break a promise to a friend, you can’t make up for it by keeping a promise to another friend. But social irresponsibility can be made up for by social responsibility. If I don’t slow down and let any drivers get onto the highway ahead of me, I can make up for it later by letting in more than usual, or opening doors for people, or giving money to the homeless man on the corner. If I buy bottled water, I can make up for it by cutting back on driving or remembering to use my recycled shopping bags. If I travel a lot, I can also pay for planting trees that soak up greenhouse gases.
I suggest, then, that having a child if you live in an overcrowded place is a water-bottles-and-travel type of civic vice, and not just plain wrong. Seeing reproduction in these terms represents a shift from tradition but not a radical shift. The civic virtues have traditionally been virtues like serving conscientiously on juries, educating yourself about the upcoming election, and taking the time to vote. Family size has seemed like a purely private matter, on a par with deciding whom to marry. But in fact, having a child is one of the most high-impact things we can do. The decision is high impact not only because a child uses up resources and produces waste, but also for a less obvious reason. Because a child is a person and not just a high-impact thing, bringing a child into the world alters the situation of every other human being. Forever more, everyone will have to treat your child as an equal member of the moral community, recognizing her rights and interests. And the same will be true of your child’s descendants.
Making a baby is private in many ways, and has a variety of very deep meanings for prospective parents—in contrast to buying bottled water, but not entirely different from travel. Thus, it seems out of the question for laws to regulate it, and not even plausible that there are moral obligations to procreate (or not). But it’s a public matter too, and it’s reasonable for there to be collective goals where total population is concerned. Thus, as part of a larger picture of factors influencing procreation, it makes sense to acknowledge civic virtues that pertain to family size. A society could send messages fostering smaller family sizes (or larger) without the messages presenting citizens with moral dos and don’ts. It’s a good thing for a nonideal family size to start seeming self-indulgent—like big cars, vast amounts of travel, and bottled water—but it would be unsupportable to transmit the stronger message that deviations from the ideal are outright morally wrong.
In the United States right now, the birth rate is 2.1 per average couple—the replacement rate—and it’s been 2.1 since the beginning of the twenty-first century. Quite possibly, that’s ideal, and total population should neither grow nor shrink; it’s up for debate, but it may be better for us to reduce our environmental impact in nonprocreative ways than to opt for smaller families. If that’s correct, we can all have the number of children we want and can support. If you have no children, enough people are having four to keep the average birth rate at 2.1. If you have eight, enough people are having none or one to make up for your fecundity. You’re deluded if you think everyone could have eight children, with no ill effects (as some pro- natalists do think), but your own eight are not a problem.
In other places, the situation is more complicated, because the collective birth rate is too high or too low. If it’s much too high, chances are that many people are poor and women don’t have equal opportunities. If it’s much too low, the lifestyle of families has somehow come to seem unattractive. Perhaps housing is expensive, or women are putting off having children too late and encountering the problem of age-related infertility.
Ethics will not be the main thing that makes a society start to hit its reproductive target, but if ethics has some small role to play, there is an alternative to making strict moral judgments. We need not think anyone is doing anything outright wrong by having a too- large or too-small family. But we do need to cultivate the virtue of social responsibility, and we need to do so even in the sphere of reproduction.