One of the most important numbers? I'd argue the most important number in computing is either 1 or 0...
wuzzlewoggle
It's called "Theory of Mind". It's basically the concept of understanding that other people know things that you don't and it starts when children are around the age of three. VSauce talked about it in one of is videos. It's incredibly interesting: https://youtu.be/evQsOFQju08?t=5m50s
I remember playing the Avatar game (the blue kind, not the airbender kind) on PS3 and at one point you have to decide in a crucial moment to continue playing as the Navi or the space soldiers, who are essentially the bad guys. But the thing was that the space soldiers where much more fun to play so I decided to play them and felt bad for the entire game lol.
I'm not saying the physical traits you are talking about aren't real. I'm saying you're using the wrong word to describe them. Biologically there is no such thing as different human races. You are talking about ethnic groups.
If you take two people from an African country they can be genetically closer to an European or Asian person than to each other.
To quote the first paragraph of the Wikipedia article on Race (human categorization):
Modern science regards race as a social construct, an identity which is assigned based on rules made by society. While partly based on physical similarities within groups, race does not have an inherent physical or biological meaning.
This. Also, he apparently still doesn't understand how tarifs work. Is he still under the impression the country he puts the tarifs on pays them and not the company who imports from them?