How do we know if vampires arnt real? or greek gods arnt real? how do we know whats true or not? how would people come up with these ideas and get it stuck in there head that it true to where the stories last for centuries after they die? dont you think there has to be some truth to all the myths out there or are we really all so arrogant to beleive were the only beings out there?

Yes. of course there's some truth to the myth, because obviously some idiot had to believe in it first to be able to tell the story... :)