 Every once in a while, someone comes to me and says, Charles, you've ignored the elephant in the room. It's population growth. And unless we control our population, then nothing else is going to make a difference. Well, I felt like I had to address that in my book because it is such a familiar refrain that I've been hearing ever since I was a kid. I read Paul Ehrlich's book, The Population Bomb, in the 1970s, basically predicting mass starvation within the span of a decade. I'm a little, so I started out, I have to confess, I started out being, in writing this book, I started out being quite uncomfortable with that narrative because it is another kind of a fundamentalism. It's another kind of reductionism. Here's the one thing that'll solve everything. And my research confirmed my suspicions. For example, if everybody on this earth lived the lifestyle of a Bangladeshi villager, the planet could support at least 15 or 20 billion people. If everybody on earth lived the lifestyle of a North American or an Australian, then two billion people would not be sustainable. Okay, that's one data point that we should keep in mind. It's that how we live is at least as important as how many of us there are. A second data point is that population growth is slowing down rapidly in many countries, if not the majority of countries were close to it. Population is at below replacement levels. Like population is gonna start decreasing in pretty much every industrialized country. And in the developing countries, so-called developing countries, population growth is rapidly decreasing as well. In some places that it's like way below replacement level. Like Japan, China, Taiwan, Korea, Singapore, Eastern Europe, most of Western Europe, Italy. It's like 1.2 children per woman or 1.3 children per woman. Replacement level is a little over two per woman because half of those will be female. And so each couple basically needs to produce two children. So then we can ask, well, why is populations growth slowing down and pointing toward a peak maybe in 2050 or 2060 followed by a long decline? And the pattern that emerges, it's not actually so much about access to birth control. The pattern is that when mortality declines, birth rates follow in one to two generations. So first mortality declines, but people are still having lots of babies. And that makes sense. If you're in conditions where half your kids die before they grow up and where people often don't make it to childbearing age, then you're gonna have a lot of kids. It makes sense to do that. And those cultural habits persist for a generation or two even after mortality plummets. So you have a population surge in that transition zone. And then cultural habits change. And it goes along with development and education and so forth. But I think really the main factor, according to some of the research that I looked into, by far the most powerful predictor is declining mortality rates. And that is happening around the world. So we're shifting from a high birth rate, high death rate society to a low birth rate, low death rate society. It's a steady state. And that brings up again the question. Okay, so if population growth is already slowing down, then the question of how we are living becomes much more important. Because like I said, if we have a steady state of eight billion people, maybe it'll peak at around 10 billion and then start declining, 10 billion is way more than enough to lay waste to this planet if we continue living the way that we are. So I think that that's what we need to focus on and not so much focusing on the number of people on Earth. And the other thing is that like this is a quantitative way of thinking, one of the themes of the book is that our obsession with quantity, with measuring things that fits so well into our problem solving modalities, our ways of addressing problems, that reductionism leaves out all of the things that are hard to measure. Like the soil organic matter deep in the ground. Like it leaves out the things that are hard to measure or that we don't even know how to measure or that are intrinsically unmeasurable. We like things that are easy to measure. That lends itself to magic bullet solutions. It's simplistic. Too much resource consumption, too many people. Solution, reduced population. And the ways in which we have done that have been quite brutal. The population control movement has a continuous history that goes back to the eugenics movement. And it was practice on pretty much the same people that the eugenicists didn't like. Especially brown and black people. So there was all kinds of sterilization campaigns where indigenous people and people of color didn't know that they were going in. When they went into the hospital they thought they were getting an appendectomy. They thought they were getting birth control or something and then they didn't know that they were actually getting sterilized. And this happened on a mass scale everywhere in the interest of controlling the population. So there's a really sorted history of this that adds to my wariness of, let's solve all the problems by addressing this one quantitative thing. And that said, I would actually prefer a world with fewer people. I like to go out into nature and not have a crowd of people visiting the same waterfall that I'm visiting. I think that it would be a lot easier to live harmoniously on this earth with maybe two billion or three billion people. We'd have more wild places. That's my preference and that is maybe part of the conversation that humanity will engage in in the future. The question isn't how many people can the earth sustain and how much do we have to limit and control ourselves to survive here? The question is again, what kind of planet do we wanna live in? What is the most beautiful vision of a future? So, yeah, those are some thoughts on population. And yeah, just to alert people to the fundamentalism that so often arises with the population conversation.