The problem is still there with any social support system for retirement: to work effectively, you need enough people paying now to cover the people on the roll

The problem is still there with any social support system for retirement: to work effectively, you need enough people paying now to cover the people on the rolls. If the population drops too much, the social safety net for retirees becomes insolvent. You can, of course, do the opposite of adding new workers: simply cause every new worker to pay more than the previous worker - but at what point do workers decide it's simply not worth it to work, when so much of their income is being spent paying for earlier retirees? It's a balancing act for sure. Previously, most western countries enjoyed a population growth, which meant more workers paying in than taking out, as this trend is reversing in nearly all western countries, it will be interesting to see how each country deals with it. In the U.S. the focus is on immigration and putting additional limits on what one can take out of the system - I'm not entirely sure that this is the right response, but I don't think simply ratcheting costs up on tomorrow's workers is the right answer either. As to robotics, well, that's a whole 'nother basket to deal with. I don't think that expanding robotics automatically creates worker revolts - if done well, it can create opportunities where they didn't exist before. Where once the only low-skilled jobs available were heavy labor and highly fungible services, we could create whole new classes of jobs relating to less fungible services (e.g. hyper-localized services), and with the possibilities of expansion off of the planet - there will be many opportunities for new work. I do believe that robotics will reach the tipping point right around the time that space exploration truly opens up. If it doesn't, my prediction that most employment will be in the armies of nations - as we fight over dwindling resources.