Studying the Bitcoin's source code for 21M cap

Recently the CEO of JPMorgan said that "I'll just challenge the group to one other thing: how do you know it ends at 21 million? You all read the algorithms? You guys all believe that? I don't know, I've always been a skeptic of stuff like that,".

Don't be like him, let's read the code and understand where this 21M comes from. ... https://www.youtube.com/watch?v=dsdW-ZaJcYA