I disagree. I'm sure it will come as no revalation to Facebook users that Facebook is not a substitute for human contact. The video suggests that Facebook users don't realise how alone they are. I don't believe this is the case. I see Facebook users post about how lonely and shy they are. They're already fully aware that they're alone. As I said, this is a revalation to no one.
As for the idea that a person can only know 150 people, this sounds like one of those facts that everyone just knows without having any proof, like the idea that people only use 10% of their brains or the idea that the Great Wall of China is the only man made object that can be seen from space.
Can you remember the names, motives and personality traits of more than 150 people? Sure you can. Even an introvert can. If you watch 20 TV shows or read 20 novels, each having 10 characters and you can remember all 200 of these characters, along with their names, motives and personality traits, you've already remembered the traits of more than 150 people.
I'm not suggesting fiction is any substitute for socialising but remembering a lot of charecters in detail still uses the same part of human memory as remembering people in real life. This part of your memory has a capacity to remember far more than 150 people, though some people you know will take up more of your memory than others.
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