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Think about the ramifications.....population explosion, overpopulation. Would we have to institute a lottery for people to have kids? Someone in your family has to die for you to get a child chit?
Finances....the problem with compounding is we spend the first 20 years trying to get to the point where we have enough cash making interests. You could now work for the first 100 years and have hundreds of millions. The entire finance model would have to be reworked.
Education/career....you could have many many professional careers in a lifespan. No more stopping education late in you career because the value isn't seen. Would we have to work forever?
Suicide.....I don't think anyone want's to live forever. What happens when people want to stop living. Do we expect them to stop taking the medicine and die in a world of 25-30 year olds of old age or do we accept suicide as the 'check out' method. See population explosion above...you check out so your great great great great great grandkid is authorized a child?