Fear of the unknown, the uncontrollable because it's unknown--some or any kind of uncontrollable-because-unknown--is the omnipresent condition of life. The belief that there is (or just might be) some sort of supernatural face that can be put on the unknown, while uncomfortable, is incomparably more acceptable to many of us than just an empty, perilous, chance universe. At least then we can imagine that we know something about whatever may threaten us.   Ghosts and other bogeys actually help us have a handle on things, and to a degree calm our fears.

Dave Oesterreich