Germ Theory in Ancient Rome?
I came by some interesting quotes by Varro.
Its pretty incredible that he figured this out. It’s a shame that a lot of his books were lost, but he was later used as a reference by people like Pliny and Vitruvius.
Many things that become breeding grounds for germs smell bad, so it was relatively easy for ancients to associate bad smells with causing poor health. Moisture, darkness, lack of ventilation all facilitate the spread of germs. It was association, not any kind of modern scientific explanation.
In fact, the word "malaria" actually derives from the Italian for "bad air"-- the mal'aria associated with marshes and swamps.
I agree, but the quotes in the OP go beyond that and specifically mention "minute animals which cannot be seen by eye". I wonder where they got that idea from.
Possibly because there was a known array of visible creatures that caused problems, from rats and mice to roaches and flies and lice down to fleas and mites. Those could be seen. So if none of those seemed to be the cause of an illness, perhaps it was an even smaller creature.
It's a step up from evil spirits, at least!
It goes further than that though. He theorizes that small animals invisible to our eyes travel through the air and enter our bodies through our noses and mouths to cause diseases.
I remember reading about an Eastern religious group that invisible evil spirits caused diseases in Antiquity. I think that it was Jainism, but I could be entirely wrong.
What if germ theory was accepted earlier?
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