Well, we are currently in the computer age which looks like it will be equal if not bigger than the previous industrial age. I believe when this paper was written, the computer age was in its infancy and the world was post industrial. As long as humans continue to innovate and explore into new areas, new ages will emerge and accelerate us forward. Maybe there will be some kind of physics breakthru which gives us easier access to space or some kind of human breakthru where we can alter our bodies. Who knows. Right, if we do nothing new, things will stagnate and eventually collapse.