The problem with the paranormal is that it's so hard to distinguish between genuine instances and "something else." The something else can be anything from incorrect perceptions of your environment (as Eddy said, your mind gets the impression it's something and believes it) to mild hallucinations caused by chemical imbalances to borderline skitzophrenia to temporary physical conditions in the brain.
The movie
Phenomenon does a GREAT job at explaining how the phyical pressure of a tumor can change the functioning of the human brain. People experience miniature strokes quite frequently and don't even know it, which can cause the most lucid and realistic hallucinations.
But this does not mean I eliminate the possibility that genuine paranormal activity doesn't occur. I'm around a lot of people with special . . abilities . . . some of them are bullshitters, some of them just **think** they have these abilities, fooling themselves as well as those around them, and some of them are blatantly honest and 100% genuine. Once I had a woman "find" a checkbook I'd lost, over the phone, from 800 miles away. I searched high and low for it for days, and she told me right where to look. I looked again and there it was. Flippin' freaked my ass out, closest I've ever come to dumping in my drawers.
IMO those that only believe in what can be proven and repeated are denying themselves a great part of the glory of this life and the universe it exists in. As Shakespeare quipped, "There are greater things in Heaven and Earth than are dreamt of in your philosophy." I DO believe this, 100%.
That being said, I can only verify one paranormal event, and it's only 80%. We used to have two cats, one was a fat, crosseyed loverboy siamese-tabby mix named Max who, when he could get away with it, would work his way up to the top of the bed, above the pilows, and crash there while we slept. One night both cats were left outside and we'd forgotten about it.
You know that feeling when a cat jumps on your bed; cat owners will know this. It's a particular plop down by the foot of the bed that can't be imitated or misinterpreted by your mate's nocturnal thrashings. I was beginning to doze off and felt a cat hit the bed, begin walking it's way up, and dozed off. Later I felt him working around the pillow, and could hear the purring. I remember this distinctly because I was too tired to knock him off the bed, this would mean I'd also have to get up and kick his fat ass out and close the door, and figured screw it, I'll just wash the sheets tomorrow.
Th next day, no Max, he was gone. Out of nowhere my wife said, "Well I felt him on the bed last night, but how could that be, we never let him in?" That kinda freaked me out too, as I hadn't said anything to her at this point. Day after day passed, no Max, he was just gone. We live in the country and presume he became coyote meat, coyotes can be real quiet if they want to and cats are great pickin's.
I've been over this a hundred times in my head, I know what I heard that night, I know both cats were out, the other one was screaming at the door in the morning. We've had other . . . ocurrences . . . but I can only say that it **felt** like something was there. This one I am sure about. So if I felt the presence of a ghost . . . it was a fatass cat, saying goodbye.
So not saying I believe you dannyd, the mind is much more impressionable when you are young . . . but not saying I don't.