Perhaps today I will link only to people named Matthew. Here is Matt Yglesias on possible fears about the future:
I understand why people worry about technological unemployment. And I understand why people worry about rising entitlement spending burdens. What I don't understand is why people worry about them both simultaneously. In the technological unemployment world, we'll be able to give everyone a 2013 level of consumption goods with a radically diminished workforce, raising the question of what everyone is going to actually do.
....The other worry is the opposite of this one. It's that in the future a very large share of our population will be elderly nonworkers and a very large share of our workforce will be dedicated to taking care of elderly nonworkers ("skyrocketing health care costs"), and that consequently younger people's living standards will diminish or stagnate.
Either of those things could happen, but they can't both happen.
Well, now, I'm not so sure about that. The question is: who will benefit from technological unemployment? Unless public policy changes fairly radically, the answer is: the owners of technology. In other words, the rich.
If technology really does keep improving and putting humans out of work, this means the rich will get ever richer. And in theory, we can tax away that wealth to take care of our entitlement problems. In theory. But I don't think it's entirely irrational to be worried that this might not be as easy as it sounds. As you may have noticed, rich people fight like crazed weasels to prevent their wealth from being taxed away. Do we think their political power is somehow going to decline as they become richer and richer?
This cycle can't go on forever. Eventually the masses will rebel, or the rich will actually get less rich because nobody has any money to keep the economy going. (Robots have no need for houses or fast food restaurants.) Or something. But "eventually" could be a ways away. In the medium-term future, both technological unemployment and rising entitlement burdens could indeed both be serious problems simultaneously.