How misinformation spreads — and why we trust it
- September 13, 2019
- Cailin O'Connor and Jim Weatherall, logic and philosophy of science, explain in Scientific American
In the mid-1800s a caterpillar the size of a human finger began spreading across the northeastern U.S. This appearance of the tomato hornworm was followed by terrifying reports of fatal poisonings and aggressive behavior toward people. In July 1869 newspapers across the region posted warnings about the insect, reporting that a girl in Red Creek, N.Y., had been “thrown into spasms, which ended in death” after a run-in with the creature. That fall the Syracuse Standard printed an account from one Dr. Fuller, who had collected a particularly enormous specimen. The physician warned that the caterpillar was “as poisonous as a rattlesnake” and said he knew of three deaths linked to its venom.
Although the hornworm is a voracious eater that can strip a tomato plant in a matter
of days, it is, in fact, harmless to humans. Entomologists had known the insect to
be innocuous for decades when Fuller published his dramatic account, and his claims
were widely mocked by experts. So why did the rumors persist even though the truth
was readily available? People are social learners. We develop most of our beliefs
from the testimony of trusted others such as our teachers, parents and friends. This
social transmission of knowledge is at the heart of culture and science. But as the
tomato hornworm story shows us, our ability has a gaping vulnerability: sometimes
the ideas we spread are wrong.
Read on, courtesy of Scientific American: https://www.scientificamerican.com/article/how-misinformation-spreads-and-why-we-trust-it/