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Suppose some incredible breakthrough in medicine was made allowing people to live for 300+ years by means of genetic enhancement or some special medicine or medical procedure. Would thus be allowed by governments? I think many would oppose extending the lives of everyone currently alive for such a long period of time, and that the human population needs to be replenished for several reasons. I hope you can identify some of the downsides of implementing such a technology, and if it would be allowed by governments.