Alan Weisman's book Countdown changed my strategy to the environment. It ranks among the top most influential works I've read, watched, or come across, up there with Limits to Growth. Why? Because when you look at environmental issues enough, and it shouldn't take too long these days, population always rises to the top as one of the top issues. Many people today hear about projections that the population will level off around 10 billion. Actually, the ones I see project that the population will keep growing exponentially then, just slower than now. If you only look at one issue---only climate, only deforestation, or only extinctions---they seem possibly solvable, but they're all linked. Solving several at once---say meeting power needs while the economy falls apart and food becomes scarce---looks impossible. Also, since nothing deliberate limits population growth, we're lucky if it levels off. We aren't choosing where to level it off and 10 billion looks three to five times what the Earth can sustain. Cultural changes could promote more growth. Many populations are promoting maximum growth today---very powerful religions and autocratic rulers for example. I don't want to rely on luck for our species' survival. Besides, my research into what Earth can sustain says that we're over the limit. If we're heading toward a cliff, simply maintaining our speed and not accelerating doesn't stop us. We have to decelerate. Despite the convergence of all these issues, for years I held back from talking about population. People don't like others meddling in their personal lives. I don't want the government in my bedroom. People overwhelmingly associate population talk with China's one child policy, eugenics, and Nazis. I did too. I didn't see how I could improve a situation by suggesting to avoid misery later through misery now. Still, I knew some cultures---island nations that lived centuries or longer, for example, or the bushmen in southern Africa whose archeological record went back hundreds of thousands of years---kept their populations level, so they must have developed some mechanism. In some past episode of this podcast, with Jared Angaza, for example, I pondered aloud how to find out how they did it, though it may have come up when I was a guest on his podcast. I could only wonder what worked but couldn't promote what I didn't know. Countdown changed all that. Alan found and reported on numerous examples in today's world of cultures lowering their birth rates without coercion, without top-down government authority, voluntarily, desired by all participants, leading to abundance, prosperity, peace, and stability, the opposite of where overpopulation takes us. Countdown tells stories of 21 places, some promoting growth and results aren't pretty and some where they've lowered birth rates and they're remarkably pleasant, even prosperous and stable. He talks about the top ones in this episode. We have tough times ahead of us. One change simplifies everything---a smaller population achieved voluntarily, peacefully, joyfully. Alan has researched firsthand more than almost anyone. He has more than enough reason to despair if he wanted to. If he's not, I conclude that everything he's found nets out to say we can do this. Family planning, education, and contraception seem technologies and practices that can work more than carbon sequestration, solar planes, and everything else. They're cheap, they're available, they make sex more fun, they've overcome cultural resistance outside the gates of the Vatican! Read his books and Limits to Growth. I'll do my best to bring him back.