The Fortune-telling
People were always thirsty for more information about the future they will have and so they invented a number of way that are likely of great help for people who want to know about their future. It is not hard to trick people because they are thirsty for being tricked and so they visit fortune-tellers for this purpose and they believe them.
It is a kind of silent deal. People know deep inside that no one is able to see the future, well there are such people but there are a few of those and they never take money for it and they never make it like show. So, deep inside people know that they will be tricked but they still go there and spend their money for lie. And the fortune-teller knows that he or she is lying though...
You see, it is like a secret silent agreement between trekkers and all the people in the world. It is the silent agreement and the matter of the agreement is lye that can calm people down. As the matter of fact the fortune-telling is always of general and the same kind for all the people who visit such a forecaster.
They always say some general phrases that means nothing indeed, and people project those phrases to their lives and they find a lot in common and they realize what the fortune-teller wanted to say. As a result a person has the information he or she (actually, she in most cases) was thirsty for and the fake fortune-teller has it money, and everyone is happy and everything is great.