This is a short book that attempts to answer the title question along with others, such as What are ghost hunters? what are psychics? what kind of haunts are there? what's the history of ghost hunting? and many others. Given this is one man's opinion, it's not what you'd call a scholarly work. What it is, is more of a rambling essay giving today's prevalent view, which you'll find on almost any ghost hunting tv show. Nothing new here, nor even very interesting.