Pixar has always had great success in cleverly flipping expected conventions on their heads. For example, making the beastly characters in Monsters, Inc. terrified of something as innocuous as a sock, their fear of children stemming from a belief that they're toxic.
But what if there was actually a serious, life-threatening cause for this seemingly unfounded fear? Well, Reddit user calabim has a pretty awesome theory that suggests that Monsters, Inc.'s scarers aren't afraid of the children themselves, but of something much more frightening: the return of a deadly pandemic that wiped out the populous of Monstropolis years before the movie takes place.
Back up, a deadly pandemic?!
To understand the theory, you have to remember that the monster world is a lot more technologically advanced than ours, having already invented inter-dimensional travel. Therefore, it's likely that the scarers, who've been collecting our scream energy for a long time, have been traveling to the human world for ages...perhaps since the Middle Ages, when the Bubonic plague swept through Europe, killing around 25 million people.
Redditor calabim writes:
A few hundred years ago, they ran their first test of a dimensional portal. The first monster to step through was probably a big hairy monster. He stepped through the door and happened into a child's room. A very sick child.
Upon seeing the monster, the child screamed, and so did the monster, who fled back into the monster realm through the portal with two things. First, the child's scream caused a reaction with the monsters' technology. They noticed a power surge at that time, as, for whatever reason, they're power source seemed to resonate with that sonic vibration.
The second was a flea carrying Yersinia pestis. He went home to his wife and kids where the flea could find a place to lay its eggs, and he didn't even think about that itch on his shoulder. Then six days later, he started to feel ill. So did his wife and kids...
'A plague spread through the monster world'
A few weeks later, the neighbors started showing signs. A plague spread through the monster world. It wasn't hard to figure out that it was that first encounter with that child that started it all.
First contact with the human world during the black death led to a deadly epidemic being unleashed in the monster world - no wonder they're so terrified of kids!
This awesome theory explains why everyone is freaking out in the clip below - the seemingly harmless sock potentially risking another infection:
It also explains why the decontamination unit from the Child Detection Agency are so keen to shave all the monster's hair off, afraid of the fleas that started the original outbreak in the first place.
Suddenly, it's a lot easier to see just why everyone's so hesitant to accept Boo as the harmless ball of cuteness she is.