A Question about Soul

Couple of things.
I had an very interesting conversation with one of my collegues about what a soul is and what it can do? I am not sure about the existance of souls. But if it exists, I am going to find out. So as ramana maharishi asked "Who am I?"

One of the most interesting books I have read in the last week is "Host". In terestingly it is about a sentinent alien beings called "Souls" who occupy the entire world by taking over the body of each and every person on the planet. I think the author is Stephenie Meyer. It talks about that doomsday scenario and how the nature of relationship between the body-mind-soul work which was exactly the conversation I had with my collegue.

Is it coincidence or does that mean there is a grand scheme of things?