Is This The Biggest Mistake Science Ever Made?

We’re pretty solid on germ theory at this point.

The idea that many diseases are caused and spread by pathogens too small to seen has been locked in since the mid 19th century.

But that wasn’t the first time  people came up with those ideas.

Physicians around the world had been theorizing about the spread of infectious  disease through invisible particles as early as the 9th century.

That’s one thousand years earlier. These scholars did everything they  could to limit the spread of infection and understand how it worked.

But if we had the basis for germ theory … by all accounts a correct idea … why did it take so long for  it to actually take root?

Well, because right ideas don’t  always win – not right away.

And sometimes wrong ideas  can be pretty convincing.

So let’s take a look at why one of  the most important ideas in biology took centuries to accept.

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Before germ theory, the main idea behind the spread of  diseases was called miasma theory.

Miasma theory says that you  catch diseases from bad air, so anything that smelled bad or  rotten was the reason you’d get sick.

In some ways, it makes sense  why people believed this.

Places that are crowded and smelly do  also tend to be hotbeds of disease.