Debate: Depopulation Matters

Abstract

Depopulation is BadOJNITCGMDMJTCPCADNFOSSDZJPBWdisagreeagreeAfter the Spike: Population, Progress, and the Case for People by Dean Spears and Michael Geruso is one of the most bracing, insightful, and important books I’ve ever read. I strongly recommend that everyone reading this sentence go and pre-order it immediately. (That’s the first time I’ve ever issued such a universal recommendation, so it isn’t cheap praise.) In my two-part review, I’ll try to convey some of why I think so highly of the book. The game plan:Part #1 (today’s post) explores why depopulation is bad. A vital corrective to all those still stuck in the 1970s “population bomb” mindset of thinking that we have “too many people on the planet already” and welcome having fewer people in future.Part #2 surveys what doesn’t work—from far-right reproductive illiberalism (which is outright counterproductive), to moderate-left proposals to financially support families (which help a bit, but still don’t suffice)—before turning to the trickier question of what to try next.The FactsEarth passed “peak baby” in 2012. Now fewer babies are born each year. Demographers expect peak population to be reached in a few decades, followed by a shocking plummet.[1] Below-replacement fertility is perhaps the simplest and most probable extinction risk around:If humanity stays the course it is on now, then humanity’s story would be mostly written. About four-fifths written, in fact. Why four-fifths? Today, 120 billion births have already happened,[2] counting back to the beginning of humanity as a species, and including the births of the 8 billion people alive today. If we follow the path of the Spike, then fewer than 150 billion births would ever happen. That is because each future generation would become smaller than the last until our numbers get very small.Something needs to change, and drastically, if humanity is to avoid this fate. (As Spears and Geruso note: “in none of the twenty-six countries where life-long birth rates have fallen below 1.9 has there ever been a return above replacement.”)Is Population Bad?I’ve noticed that many—esp. older—academics seem stuck in the mindset of worrying about “overpopulation”, and hence welcome the prospect of depopulation. The crux of the disagreement may come down to a pair of empirical and ethical disputes:On present margins, do people on average have more positive or negative externalities? (Empirical question about causal-instrumental effects)Do human lives, on average, have intrinsic value? (Ethical question)The bulk of the book is dedicated to answering the empirical question, and allaying the concerns that lead too many to curse humanity and wish for fewer of us. I won’t be able to do their comprehensive discussion justice here, but just to flag a few highlights:Climate changeThe most commonly-expressed concern is, of course, climate change. And here, Spears and Geruso have an absolutely decisive response: timing is everything, and depopulation is too slow to help. We need to decarbonize over the coming couple of decades. Depopulation after 2080 (or whatever) won’t help with that. If anything, it may just make things worse (as society shifts more and more of its limited resources towards