There are many ways for communication to break down. Some thinkers have suggested that people with very different intelligence levels cannot interact effectively. They have even put a number to it: communication crumbles when there is a difference of 30 IQ points between two people.
That sounds sciencey, right? It’s a specific number and everything.
Of course, anyone with experience interacting with other people probably knows this is hogwash. Even the most intellectually gifted person can enjoy the company of—and learn a lot from—a person who sticks to simpler cognitive pursuits, and vice versa.
The myth appears even more unlikely when you consider issues with the very concept of IQ. Intelligence is a lot more complicated than a single number, and cognitive performance changes from day to day, so this +/- 30 number would be imprecise even if it were real.
A blog post on Neuroskeptic looks into the origins of this idea, and finds that not only has it been misinterpreted and twisted over the years, but it was never based on science to begin with. Someone just made it up.
There is a broader lesson here: don’t assume something is scientific just because it has a number in it. It’s just as easy to make up a number as it is to make up anything else. 9 out of 10 doctors agree.