From the USTC, I recently learned that only 30% of books published between 1450 and 1700 have been scanned — and fewer than 5% translated (most are in Latin). So, we have some work to do: https://www.ancientwisdomtrust.org/
Huh, this paragraph caught me - I was recently involved with a group using large-scale environmental metagenomic sampling to try to find good candidates for a drug discovery pipeline. The working theory was that bacteria use chemicals to fight off attackers, and if the bacteria was going to produce potentially lethal amounts of a substance designed to kill other bacteria, it would need a "sink" for that substance as well, and that would likely be co-located in the genome (so when the gene for the dangerous chemical gets activated, its sink is likely to get activated as well) - so, find something in the metagenomic library that looks like the substance causing you problems, and then look nearby for something that might be a cure. Funny to revisit this kind of observational thinking from a more modern perspective.
Salicylic acid from willow bark has been known for millennia. But the side effects to the stomach are not good. Aspirin came along when enough was known about the chemistry to try to deal with the side effects. Aspirin is salicylic acid with an acetyl group hung on to reduce the side effects.
Tweaking small molecule drugs to work better or have fewer side effects is common today. Aspirin was one of the first early successes.
The level of focus, will, and commitment to continue to chase things into the dark.
What luxury we have today to have such information at our finger tips. Just really incredibly to think on