It’s tempting to embrace the meme that the best way for humans to solve the big problems in front of us is to increase the population, perhaps dramatically. The thinking goes that people are the ones who can solve problems, and more people give us more problem-solvers.
This doesn’t hold up to a reductio ad absurdum analysis: clearly, a population of 10 people isn’t as good at solving problems as one with a billion, but at the same time, if there were a trillion people on Earth, that wouldn’t last long. There must be a number that’s optimal, but it’s probably not the biggest number we can possibly create.
And reviewing the data on Nobel prizes per capita, or patents per capita, we see that there isn’t a correlation between population density and productive breakthrough innovation. It looks like innovations are more likely the result of a civil society, sufficient resources, enough productivity to enable spending on R&D and a culture of research and engineering.
We also see geographic hotbeds of innovation over time (physics in Germany a hundred years ago, or network innovations in Silicon Valley a decade ago) that are the result of information exchange and cultural expectations, not population density.
We don’t get these results by stretching the carrying capacity of our one and only planet. We can’t shrink our way to possibility, but we probably can’t get there via exponential expansion either.