I grew up during the Cold War, when everything seemed very tenuous. For many years, right up until the fall of the Berlin Wall, I had vivid nightmares of nuclear apocalypse.
I used to look at horror movies as being really real and it would totally freak me out and give me nightmares. Now I watch and think, 'whoa how'd they do that?'
I believe in everything until it's disproved. So I believe in fairies, the myths, dragons. It all exists, even if it's in your mind. Who's to say that dreams and nightmares aren't as real as the here and now?
I used to have nightmares when I was a little kid that I woke up prematurely and opened all the Christmas presents. And then I would be so relieved when I woke up and I realized that I hadn't done it.