One of the interesting things about the paranormal is how many people have stories and experiences of it, like ghosts as an example. I never seek to deny that people have had experiences that they are unable to explain through normal science. That's not to say such experiences are unexplainable though.
One thing I do know is that 'seeing' is not always a case for believing. Every humans brain is unique and processes the information from their senses slightly differently. And there are all sorts of things which can affect how our brains process the information. All of us know that drugs for instance, especially hallucinogenics, can greatly effect how our brains process what we see. Other simpler things though like stress, strong emotions, lack of sleep, etc can also alter our brain chemistry and thus alter the way our brains process information. Some years back I did some work within a psychiatric ward in a hospital and some of the patients there certainly perceived the world around them in completely different ways than most of us would.
Also our upbringing and belief systems can greaty affect how our minds construct an image from what our eyes see. The point being that if you are open to the existence of ghosts then you are much more likely to see one at some stage than someone who is not. You can have 2 people see exactly the same thing and their minds can interpret what they see completely differently.
So I know that many people strongly believe that they have seen ghosts or other paranormal events and although I don't deny that is what they have seen I do not believe it provides any sort of objective or conclusive evidence for the existence of such things. Our minds work in mysterious ways!
