Doing any sort of work is a constant process of invention, as you solve all the little problems involved. This other post linked from the article is a good read: http://johnsalvatier.org/blog/2017/reality-has-a-surprising-...
> the people living in them actually seem to have quite a bit of free time, yet obviously technological innovation has been quite rare.
I have to wonder if it is the people that have quite a bit of free time there, or men only.
I can see men having not much to do once they hunted and brought their prey. But if women are left with the task of preparing food from such completely raw ingredients, and also have to do childcare, possibly some gathering in addition, they don't have much time in the day left.
(I'm no farmer but) From what I hear, farming is characterized by periods of very hard work followed by long winters that you spend mending tools and clothes. I think a farmer could have had enough free time to invent, say, a plough.
Perhaps hunter gatherers are generally content with their existence and see no need to invent, whereas farmers and agricultural societies are frequently unsatisfied and unhappy (because they spend more time working and less in recreation) and are therefore more motivated to try to change their circumstances.
Also I would imagine that incremental improvements to tools and methods have the potential to benefit farmers much more than hunter-gatherers. So even given the same amount of free time, farmers have more incentive to tinker.
In a subsistence farming environment it seems true that people did not have much time or resources to devote to making inventions. However, from what I've read of hunter-gatherer tribes still around today, the people living in them actually seem to have quite a bit of free time, yet obviously technological innovation has been quite rare.
So is it the case that innovation happens in a fairly specific set of circumstances, where resources and time are scarce enough to make innovation necessary, but still plentiful enough to allow for innovation?
Or maybe its just that the type of civilization agriculture creates leads to sufficient population densities for knowledge to start accumulating.