Societies tend to go through faster periods of inventions when certain conditions are met. One of them is war, that drives inventions.
Another one is a more equal society. In societies where you get to use your invention yourself and benefit from it yourself there is more incentive for more people to do it. If your invention is mainly going to benefit elites, fewer people spend time inventing. This is one of the reasons why empires historically stagnate towards the end.
@afraid_of_zombies
Inventions are cumulative.
Societies tend to go through faster periods of inventions when certain conditions are met. One of them is war, that drives inventions.
Another one is a more equal society. In societies where you get to use your invention yourself and benefit from it yourself there is more incentive for more people to do it. If your invention is mainly going to benefit elites, fewer people spend time inventing. This is one of the reasons why empires historically stagnate towards the end.