This Sustainable Life


294: Population: How Much Is Too Much?

Ep. 294

What is Earth's carrying capacity? Why is it important?

Many ask how we will feed 10 billion people. Mathematician way of asking is if we can feed so many and if so how. Maybe we can't.

First, don't want to know. While it depends on many assumptions that aren't hard or measurable numbers, like standard of living, distribution of resources, and technology, we can say it's maximum misery per person.

How do we narrow it down? Could ask resources per person and how much resources Earth can provide. Limits to Growth projects how much planet would sustain from a systems perspective including history and how we live our values.

I prefer a historical perspective I learned from Alan Weisman based on the Haber-Bosch process, which enabled artificial fertilizer. Before artificial fertilizer, limitations on fixing nitrogen to grow food suggest Earth could sustain about 2 billion, enough to create Einstein and Mozart. Want people like Jesus, Buddha, Laozi, and Aristotle? We needed only a few hundred million to create them.

If we're over the planet's carrying capacity, especially by factor of 3 or 4, strategy isn't to ask how to feed 10 billion but if we can lower the population before processes like famine, disease, loss of critical resources, war, and so on do it for us.

I couldn't answer except in ways where the cure was worse than the disease, but the history of Thailand's Mechai Viravaidya's leading a nation-scale cultural shift from 7 babies per woman to 1.5, voluntarily, peacefully, leading to abundance, prosperity, and stability changed everything for me.

Mechai's success makes lowering the population plausible and fun. The limitations of growing food without artificial fertilizer make it necessary to avoid famine and other natural disasters. These two factors clarify our priority, it seems to me.

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487: Karen Shragg E.D.D., part 1: At last, simple, reasonably talk on (over)population

Ep. 487
We can dance around our environmental problems all we want. Understand them enough and we eventually reach overconsumption and overpopulation. These overshoots contribute to everything.We at least talk about overconsumption, even if few are acting. Decades ago, the public talked about population, but didn't act. Today we don't talk about it. All the numbers I see suggest the Earth can sustain two or three billion people with roughly western European consumption levels. I'd love to live in a world with two billion people, like what produced Mozart and Einstein.Karen has been working on helping society face our problem of too many people being alive at once longer than I have. I've only been able to talk about it since learning from (TSL guest) Alan Weisman's Countdown about (TSL guest) Mechai Viravaidya helping solve the problem. She's been treating it a lot longer. She also knows I think all the podcast guests I talked to about population. She also knows many environmentalists who never acted on population.Karen shares her decades of working on (over)population. The U.S. doesn't talk about it publicly these days, but Karen shows how to talk about it. As I recognized that our overpopulation contributes to every environmental problems, I realized we had at least to talk about it. Karen does this.Karen's page: Moving Upstream... Where Possibilities Come to RoostMove Upstream: A Call to Solve OverpopulationChange Our Stories, Change Our World