Yea but for routine consumption, drinking exclusively hot (boiled previously) water wasn't as much of a thing, especially in Northern China, prior to like mid 1800s.
It was after a particular outbreak (cholera?) somewhere in the 19th century that hit northern China way worse than southern China that they figured out the major difference was the hot water habits in the South. Even in the 1930s there was still a push to increase boiled water usage.
Sometimes people do things for a certain reason but it can also have other positive effects. In a way, it doesn’t matter why a trait or behaviour spreads, as long as it’s beneficial.
I don’t disagree with your sentiment but the literal topic of conversation here is the “why” part.
Sometimes conversations can have practical applications. Other times they’re just academic for academics sake. But both are perfectly fine conversations to have.
But humans have been cooking stuff for thousands and thousands of years to improve nutritional value and kill off bacteria. Why would water be an exception?
Bacteria wasn’t known about thousand of years ago. Nor were nutrients (in the sense that we know it now).
There are a plethora of other reasons food might have been cooked, not least of all being flavour. The fact that it also killed bacteria would have been an accidental benefit.
Also a lot of food actually loses nutrients when cooked.
Ancient cultures relied on observation-based trial-and-error knowledge passed down from generation to generation, mostly involving people dying. They didn't have to understand the causes in order to be correct about the effect. E.g., if you eat raw meat that's been sitting there a while, you get sick and might die. How do we know? Because X and Y people died after eating it. But if you cook it, you don't get sick and don't die. How do we know, because A and B people cooked it and didn't die. Thus -> cook meat. Why? Who knows what unscientific reasons they would give (likely superstitious ones). But "discoveries" of this sort were passed down, in the same way that they discovered which mushrooms not to eat (by people dying when they ate them).
Same applied to which local sources of water were safe to drink (i.e., people didn't die when they drank from there), and whether fermented drink (i.e., beer) was safer than water.
They are. But the solution to each might be different. And given the specific argument being contested here is whether beer was drank because it was considered safer, understanding their motives is pretty fundamental to that discussion.
The motives don't always have understanding of the root cause however. We knew that eating raw meat was unsafe even though we didn't know about salmonella.
That's exactly my point. This whole conversation is about whether beer was drank because water was unsafe. Understanding what their understanding of "unsafe" was, and what they considered the remedy, is central to this discussion.
Being smart and knowing stuff are not equivalent. The smartest person alive 300 years ago had no clue about bacteria and viruses. Or anything like horizontal gene transfer. Sure, they were not stupid. They still did not know a lot of things, which occasionally made them do stupid things. For example, it is well documented that people believed diseases were transmitted by “bad air” (i.e. pestilence, or bad smells) up until the mid-19th century (not to mention demons). They were not stupid, but there were some things they did not know.
I am not saying that we are any better; there are a lot of things we don’t know that will be taken for granted in 200 years. If there is still a human race.
> For example, it is well documented that people believed diseases were transmitted by “bad air” (i.e. pestilence, or bad smells) up
But that's not particularly stupid. Bad smells are certainly a proxy for diseases to some extent and avoiding them/removing their sources would also decrease the likelihood of getting sick.
> Bad smells are certainly a proxy for diseases to some extent
No, they are not. Because smell and germs are completely unrelated. There is a limited case where they are correlated (don’t play with organic waste or too old corpses), but even then it is not really helpful. This is why it took so long to understand how to stop cholera: you can have things in your water even if it looks pristine. The air is just a red herring.
It is not even helpful with airborne pathogens, as once they start spreading among humans all bets are off.
> Bacteria wasn’t known about thousand of years ago. Nor were nutrients (in the sense that we know it now).
And yet, processed like nixtamalization (the processed used to make the nutrients in maize available to humans) were discovered over 3000 years ago.
If ancient humans figured that complex process out, they certainly would have been able to figure out that boiling water made it safer to drink, even if they didn't know why. They'd probably just claim it killed the evil spirits or pleased the water god and have been happy with that explanation.
If someone is going to go through the process of boiling water, they might as well throw some stuff in there and turn it into soup/tea/broth/stew/whatever so that it tastes nice and makes you less hungry.
To accurately gauge if something is safe, you need a quick and direct result that is consistent. Unsafe food and liquid isn’t that. Often it’s more a percentage problem. So to solve the percentage problem you then need a larger sample size. And people simply weren’t organised enough to accurately measure at that scale in the periods you’re suggesting.
As an aside, this is why people got thrown into volcanos and such like. If you don’t have measurements that are easy to correlate then you’re effectively left to guesswork.
There’s a lot of knowledge we take for granted that simply hadn’t been discovered yet in medieval times.