before that, let us define ghost... most of peoples definition of ghost is that there are being who passed away from human and remain in earth realm..

some might call them ghost, spirits, zombie, jin, orang minyak, guardian of things, demon etc etc.. every culture has their own name and looks and characteristics...

however, I used to have a friend who claimed that he has the ability so see ghost... from our conversation, they looked like shadow.. blurred... like human, some are good, some are bad...

the question here... how come some people are able to see them while other are not able to?