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> I'm not sure which definition of 'growth' you're referring to here. One in which brain uploads are relevant, because you mentioned it. Literally any kind of efficiency has a maximum, an economy of pure minds was just the most extreme case which I took specifically to avoid any possible debate: there is (according to currently known laws of reality) definitely an absolute maximum in this universe, no matter what we do. Limit the population to current number or lower, and any other kind of efficiency also has a limit — lights can’t convert less than 0% into heat, resistance can’t be less than in a superconductor, reversible computers can’t beat the Landauer limit. You might fully automate manufacturing and give everyone alive today their own personal galaxy cluster [0] and it’s still finite. Big, still finite. > If it's GDP (which the article linked earlier did), well, in many developed countries, population has been decreasing despite increasing GDP. So this issue does not prevent growth. Indeed it is decreasing. Yet you may have to enforce that, because subgroups that grow faster rapidly dominate. This is unavoidable unless you take active measures to prevent it, because that’s what evolution does. (You can because evolution is dumb, but you have to). (I’d argue that in such a case, the license to reproduce would constitute a currency and in that currency humanity today world seem unimaginably wealthy; however this is not something I am prepared to make a keystone argument)