Why Did People Think Bad Smells Caused Disease?

Why would anyone believe that a smell could make them sick?

Before scientists understood germs, the evidence seemed to point that way. Filthy streets, rotting waste, and overflowing sewers smelled terrible, and people living around them often became ill.

If you couldn’t see the bacteria in contaminated water, but you could smell the sewage, wouldn’t the air seem like the obvious suspect?

This belief was known as miasma theory. Although mistaken about how diseases like cholera spread, it was based on a real observation: unsanitary places could be dangerous.

What I find fascinating is that the reasoning actually makes sense when viewed through the knowledge available at the time.

It makes me wonder how many things we confidently believe today simply because we haven’t discovered a better explanation.