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For some time, I’ve been attracted to the “it’s the phones” explanation of fertility decline. One counterargument is that fertility has been falling since the 19th century. But that fact actually supports the claim that iPhones are causing the recent collapse in fertility. To see why, consider for a moment why smart phones explain declining fertility.
It’s misleading to call smart phones a “phone”. They are a mobile general purpose entertainment center, with phone calls representing just one use among many. They also represent the culmination of a set of changes over the past 200 years that have made life increasingly fun, but also less social. I see four major changes:
1800-1920: Urbanization. City life is more interesting than rural life, leading to smaller families. (In addition, improved health care and sanitation means that fewer children die.) Here’s Noah Smith:
Urbanization disrupts the need to grow your own community, by giving you a community of strangers. Fertility rates have always been much lower in cities than in the countryside, and when countries become more urbanized and wealthy, their birth rates drop.
1920-1930: Movies and radio. Most people are lazy and vastly prefer consuming stories without having to read a book.
1955-1975: Television. TV brings movies into peoples’ living rooms.
2010-today: It’s the phones.
Unfortunately, this Statista graph stops in 2020, and thus understates the recent decline in US fertility, which is now below 1.6:
When you look at the graph, be aware that some of the volatility reflects transitory factors such as the Depression and World War II. Nonetheless, some interesting patterns are worth commenting on. The 1920s saw a particularly rapid decline in fertility, perhaps due to a particularly rapid rise in fun. Here’s AI Overview:
The US general fertility rate (live births per 1,000 women aged 15–44) steadily declined during the 1920s, moving from 117.9 in 1920 down to 89.3 by 1929.
When I read novels from the post-WWI period, they occasionally discuss the rapid cultural change among the young, partly under the influence of Hollywood films. Instead of going right from childhood to adulthood, there emerged a long period of transition, with loosening cultural restrictions on the lifestyle of young people. New forms of entertainment like radio and movies made urban life much more interesting for most people. Even 100-year old silent films are quite entertaining.
Another big fertility decline occurred between the mid-1950s and the mid-1970s, probably due to television. And then fertility in the US leveled off for more than 30 years. The post-2010 decline is global in nature, which points to “the phones” as the most plausible suspect.
For most of us, family life is now just one part of our life. But for most of human history, family life was almost everything. The family unit worked together and played together. Before TV, radio, and film, social life was the main form of entertainment. Larger families were more fun, less lonely.
So, when people say, “it’s the phones”, I think they actually mean “it’s the fun”. Fertility is declining because we’ve invented technologies that we find more fun than traditional family life. It’s not that family life is becoming less fun, it’s that the enjoyment of family life is staying constant as alternative activities become ever more attractive. The opportunity cost (in foregone fun) of family life is increasing.
But that does not mean that higher fertility is a lost cause. People still do place some value on family life. And people who are rich enough to have servants do all the hard parts of raising children tend to have relatively large families. In the US, billionaires have larger families than middle income people
In the future, plentiful AI-enabled robots may contribute to childcare, making us all billionaires. Here’s The Economist, discussing the views of Elon Musk:
Mr Musk predicts that, within five years, artificial-intelligence systems may surpass the sum of all human intelligence. Within ten years, robots in the workplace will help usher in an era of such “amazing abundance” that money will become meaningless.
I can hardly wait! Oddly, Musk worries about fertility. But if Musk is correct about our future limitless wealth, then we may soon resume worrying again about “overpopulation”. Why does Musk not believe that average people would react to great wealth the way he and his fellow billionaires have responded, that is, by having bigger families?
PS. To be clear, I’m not anywhere near as optimistic as Musk about the near future, but I do expect future generations to eventually become quite rich by today’s standards, mostly due to AI.
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