Blind
Only Settle for Victory
I'd say it's more likely that neither exist.
A.) It's not like aliens are landing in our back yard and asking if they can borrow a cup of sugar. I'm sure we could have had some real, solid evidence by now if they did exist and were as intelligent as Hollywood would like us to believe they are. There may be some slug somewhere on the backside of Pluto or some weird planet far, far away, but intelligent life, I highly doubt exists - at least the way many people wish they would exist. Besides, if you buy into evolution, do you realize that the chances that a tree evolving, alone, without outside help from a higher source, are mathematically insanely high? So the chances of other civilizations, other aliens, all "accidentally" appearing over and over and over all over the universe - well, scientifically and mathematically, if you believe evolution, the equations get much bigger and harder to buy into.
Ghosts - okay, seriously people. Maybe there's a demonic force or something - yes, I said demonic, but I guarantee 9 times out of ten all "ghost" stories are made up of someone's own paranoia. Not the paranormal.