[stefl14]

> More people means less energy and resources per person though

Malthusianism didn't work in 1700s and doesn't work now. Economists produced endogenous growth theories explaining how more population could lead to higher output per capita in the 80s. Romer won a Nobel prize for it.

The evidence we have now strongly supports their arguments. Productivity scales superlinearly with urban population so that each doubling leads to a 15% increase in p.c output. This is true everywhere we look i.e. regressing log(income per capita) on log(city population) produces near-perfect lines with slopes close to 1.15 whether you're looking at the U.S or Bangladesh. This is easily explicable in terms of the network externalities. Furthermore, studies comparing the networked lives of people living in more/less populous areas (inferred from phone usage data) show that people living in bigger cities do indeed communicate more. How much more? 15% for every doubling of city size! All of this can be explained in terms of graph theory. More nodes -> more cultural and technical niches (interconnected node clusters) -> more potential synergies as every niche has more niches to connect to. And so on. Connectivity increases faster than linearly, hence the superlinear scaling. Not coincidentally, the connectivity of brains seems to be the same (double the number of cortical neurons in a mammal, the number of synapses per neuron increases by 15-20%).

All this to say, we certainly aren't approaching a world of less abundance per capita as the world continues to urbanise. Anybody who thinks this just isn't acquainted with the evidence.