In the summer of 1975, Stephen Spielberg released Jaws – an iconic film about a seaside town terrorized by a great white shark. It was a box-office hit and an exciting summer distraction for many movie-goers. It also had a powerful, if not totally unexpected, side-effect: it made some people afraid to swim in the ocean.
People knew the story was fictional. And, if pressed, they’d acknowledge that the likelihood of a shark attack didn’t increase during the 2+ hours they were in the theatre. And yet, people who had no problem going into the ocean before were suddenly afraid to do so. What happened?
In the past, when these people were swimming at the beach, they thought about things like the temperature of the water, the heat from the sun and the people swimming nearby. But they probably didn’t spend much time thinking about sharks. After seeing Jaws, they could think of nothing but sharks. The idea of Jaws coming at them from the depths seemed vivid, terrifying and suddenly very likely. In reality, the likelihood of a shark attack was, and continued to be, extremely low. People who stopped swimming in the ocean after seeing Jaws simply fell victim to the availability bias.