That point doesn't seem particularly intuitive to me. A society in population decline is a society where the old outweigh the young. You would seemingly have a

That point doesn't seem particularly intuitive to me. A society in population decline is a society where the old outweigh the young. You would seemingly have a higher ratio of long-term experts to young learners than you do under a population growth scenario. If there is a risk, your risk isn't that you have too few experts to offer training, it's that the young learners are spread too thin. There aren't enough people looking to learn for all the people who have knowledge to pass down and so you lose knowledge in that transition. -------- With that said, I find the general premise that we would be looking at some kind of dark age with the level of population decline any of us are likely to see in our lifetimes, nearly comical. The global population now is around 8 billion. It was around 3 billion in 1960 (4 billion in 1974, 5 billion in 1987, 6 billion in 1999). It doesn't seem to me that the pace of change or technological advancement was particularly slow in any of those time periods, and the substantial productivity gains since then would alone suggest that we'd be more efficient for those population levels than things were at that time.