The benefits of population growth come from the fact that the more people there are in the world, the more people you have to interact with, the more potential friends you have, the more potential mates, the more potential business partners, customers, employers, employees. But even more than any of that is the fact that we all free ride on each other’s ideas. Virtually all of our prosperity comes from the fact that each generation free rides on the ideas of the previous generation, and improves on them — not just uses those ideas in and of themselves, but uses them to inspire the next generation of ideas. We use them to build on and to make the world a more prosperous place. A lot of that is invisible. You have all this technology around you and you tend to forget the fact that had there been half as many people, there would have been half as many ideas — probably fewer than half, in fact, because ventures actually inspire each other, so there’s a more than linear buildup of ideas as the population grows.I like to say that when you’re stuck in traffic on a hot summer night, it’s very easy to remember that the guy in front of you is imposing the costs, and, unfortunately, you also easily forget that the guy who invented air conditioning has conferred on you quite a benefit. You remember that if the guy in front of you had never been born, your life would be a little easier right now — but it’s also easy to forget that if one less person had been born it might very well have been the guy who would’ve invented air conditioning, not the guy who’s in front of you. So, the real way in which people get this wrong, I think, is that the mind immediately goes to the fact that there is such a thing as too large a population. And there is such a thing as a population so large that the earth cannot support it — we all know that. But that does not address the question of whether the current population is too large or too small. And somehow people often confuse one of those questions with the other. I’m not sure why, but I’m out to unconfuse them.
This excerpt is from the interview of author, blogger and professor Steven Landsburg by the Richmond Federal Reserve (hat tip Bob Murphy)