I kind of lean more to the side of "yes" with this one. I have heard of way too many accounts of ghost sightings and encounters and I know that while some of them could be lies, it's unlikely they were all lies. Any one that says no should have a heart rate monitor strapped to them and be pushed to walk through some haunted mental hospital or something like that. At night, of course. One of these places could suffice too. I'd be very surprised if they still only had indifferent reactions and their vital signs stayed the same during the whole trip through.

Because of all this, I don't mess with that kind of stuff.