This strikes me as very naive. Birthrates have been declining for a few decades (in some countries) and you're trying to extrapolate this trend out into the distant future. Meanwhile there are already developed countries that buck this trend. Qatar is richer than any European country, and Qataris have 4 kids per woman. Imagine you had a petri dish of bacteria, and introduce a chemical that stops reproduction of 98% of the types of bacteria inside it, 2% of the bacteria have resistance to this chemical. What you would see is a period of slowing growth, as most of the bacteria stop reproducing. Then there would be a period of decline in the bacteria population, as the non-reproducing bacteria start dying off. Finally, there would be a return to exponential growth, as the 2% fill the petri dish left empty by the sterilized bacteria.
All that is necessary is for a small percentage to be immune and to be able to pass their immunity to their children with some consistency.
Well, Qatar's birthrate is in a decline, too. But that's beside the point, since I don't actually disagree with you. Both your comment and mwengler's reply strike me as arguing a different point from what I was making in the essay.
I was primarily trying to say that life extension won't cause an immediate economic disaster - that yes, although it will impact global demographics, it will take many decades (maybe centuries) for the impact of those changes to propagate through society, which is plenty of time for our economy to adjust. Dealing with gradual cha...
I might need a better title (It has now been updated), but here goes, anyway:
I've been considering this for a while now. Suppose we reach a point where we can live for centuries, maybe even millenia, then how do we balance? Even assuming we're as efficient as possible, there's a limit for how much resources we can have, meaning an artificial limit at the amount of people that could exist at any given moment even if we explore what we can of the galaxy and use any avaliable resource. There would have to be roughly the same rate of births and deaths in a stable population.
How would this be achieved? Somehow limiting lifespan, or children, assuming it's available to a majority? Or would this lead to a genespliced, technologically augmented and essentially immortal elite that the poor, unaugmented ones would have no chance of measuring up to? I'm sorry if this has already been considered, I'm very uneducated on the topic. If it has, could someone maybe link an analysis of the topic of lifespans and the like?