In the debate over the housing shortage and western public lands, many people argued that if immigration were slowed, that would fix things. But even with no population growth there would be a housing shortage, because household sizes are shrinking. We would still have to build.

Housing in Singapore is abundant and costs locals very little, thanks to Singapore's generous and high-quality public housing system. Yet Singapore's fertility was just 0.97 in 2024. Apartments in high-rises aren't well suited for families no matter how affordable they are. 1/3

"I just noticed that low birthrates are a problem two minutes ago, but having tried almost nothing, I conclude that nothing works." Here is a list to start with. None of these are incompatible with a free, liberal society.

Extraordinarily low birthrates are being recorded in 2025. Demographers define "ultra-low fertility" as below 1.3 births/woman -- some 29 countries were that low. Countries at ~1.0 or less: Lithuania, Poland, Costa Rica, South Korea, Taiwan, Hong Kong, Thailand and Singapore.

Co-author of Superabundance @Marian_L_Tupy explains the counterintuitive fact that resources became MORE abundant rather than scarcer as populations grew, because of greater numbers of smart people working together. But that means that population decline will make us all poorer.

I have a great discussion with @aaron_renn on why the birthrate crisis will be more severe than most people realize, what the major drivers are, and most importantly, what are some ways to turn things around, especially in policy. Link below, please share!

US government models, similar to the UN, assume that birthrates will just magically recover, even though they keep going lower. Although fertility rates have fallen to around 1.6, models assume fertility returns to 1.9 by 2050. @TPCarney notes that such a recovery is unlikely.

An important new paper by Geruso and Spears looks at how much of fertility decline is explained by childlessness versus smaller family sizes. "Childlessness explains only 38% of the decline in fertility in the advanced economies." This implies larger families may hold the key! 🧵

Imagine something that causes people to have more kids, but the strongest effect is on the smartest people. Interested? That's what religion does! See this chart.

On this Father's Day, let's think of young guys and the future. How can young men, most of whom really want children one day, boost their odds of achieving fatherhood? 🧵!