This is hidden brain.
I'm Shankar Vedantam.
During the Middle Ages, word spread to Europe about a peculiar plant found in Asia.
This plant had a long stalk with heavy pods attached.
When you cut those pods open, inside you would find a tiny little lamb.
Complete with flesh and wool, like a live animal lamb.
This creature, half plant, half animal, came to be known as the vegetable lamb of tartary.
Various travel writers wrote that they had either heard about this or that they had eaten one of these lambs.
And many of them said they had sawn the kind of downy wool from the lamb.
When these narratives made their way to Europe, people felt they, they had a view of a different world.
Of course, no one in Europe had ever seen the vegetable lamb of tartary because there was no such thing.
But for centuries, people kept talking about this fantastical creature as if it were real.
It even came up in scholarly works right next to pictures of oak trees and rabbits.
If people hadn't been telling each other about these things, nobody would believe that there were vegetable lambs because nobody had ever seen them, right?
And this is by no means a unique happening at that time.
At that time, of course, we would never fall for vegetable lambs.
We live in an era of science, of evidence based reasoning, of calm, cool analysis.
But maybe there are vegetable lambs that persist even today, even among highly trained scientists, physicians and researchers.
Maybe there are spectacularly bad ideas that we haven't yet recognized as spectacularly bad.
This week on hidden brain, were going to look at how information and misinformation spread in the world of science, and why evidence is often not enough to convince others of the truth.