Earlier quoted context omitted.
> Knowledge steadily accumulates over time. No, it doesn't. Only knowledge that people consider to have value will be retained over time. Many things are lost to history, for example.. nobody knows how to make cobblestone. (Or so I'm told)
One of the scariest things I ever read was the true story of how the British Navy discovered and then lost the knowledge of how to cure scurvy. IIRC, they found that limes (or lemons) would prevent scurvy on long voyages; then the ships got faster AND the switched to a citrus fruit lemons (or limes) that didn't have enough vitamin C to prevent scurvy, but they didn't realize it because the faster voyages didn't allow…
Admirals resisted submarines and carriers until catastrophe forced their hands.
Most people don't realize that scurvy had actual fatalities on most British ships that went on long voyages.
Similarly, in Japan in the late 1800's, deckhands had a ration of free rice (mainly carbohydrates), so that's all they ate. As a result, there were ships half full of sailors laying ill from almost no vitamins, mainly B1, resulting in beriberi.
That continued with the army into the early 1900's:
https://medium.com/war-is-boring/eating-too-much-rice-almost...