Superstition

I am not a very superstitious person but when I overheard a mother telling her son not to open an umbrella indoors it got me thinking. I want to know where all these rumors start. Example: Opening an umbrella indoors, carrying a horse shoe, four leaved clovers, etc. Are they real or are they not?
I wonder if the rumors started to be completely different than what people believe today. Example if somebody said opening an umbrella indoors will protect you from the bad luck on Friday the 13th. People would get the story completely wrong due to miscommunication or anything else. I often wonder if it was our ancestors who started these rumors... Turns out they did. . I also wonder how long people have been following these superstitions. Superstitions began centuries ago when our ancestors tried to explain  mysterious circumstances or events as best as they could with the knowledge they had.
    For instance, before the development of science explained such strange things as why mirrors show our reflections or why shadows appear when it's when it's sunny, ancient people reasoned that a shadow or reflection was a part of their soul.
  If someone broke something onto which the shadow or reflection appeared, people believed that their soul was harmed. Therefore, when a person broke a mirror it was considered unlucky or harmful.
    This a list of common superstitions.
 1. Walking under a ladder will invite bad luck.
 2. Breaking a mirror will bring you 7 years of bad luck.
 3. It's bad luck to have a cat cross your path.
 4. Seeing a shooting star will bring you good luck.
 5. The number 13 is bad luck.
 6. Carrying a rabbit's foot is good luck.
 7. When visiting someone, leaving through a different door you came in is considered bad luck.
8. If you step on a crack you'll break you're mother's back.
If it rains on your wedding day you will be showered with good luck.

The thing that confuses me the most is that if it's true or not. I guess superstitions will be one of the unsolved mysteries of the world.

While I go figure out more about superstitions.. enjoy this song.