Writing ghost stories

I've been thinking about this lately: how fun would it be to write ghost stories, like really scary stories that give people the creeps, make them want to not leave their rooms at night, not read the stories in the evening, make them feel all weird and uncomfortable. How cool would it be to make people question and re-question their reality, to scare people who don't believe in ghosts but are still afraid of them, in sense of 'spirits' and 'presences' and as such.

They say ghost stories are not about ghosts, they're about the fear of the unknown. The floating white thing in the air is a known thing...what's really scary is the thing that's underneath -- something that you can't explain or logic about. You don't know what it wants or what it's going to do next, you can't really model its behavior. In fact your entire understanding of world discounts the presence of very such force, which makes you question both your senses and your sanity. If you can't trust your eyes and ears, sight and sound, you can't trust the cold chill on your skin, what can you trust? The world becomes a lot more unpredictable and uncertain place, you are like a little child exploring the unknown, every little movement or motion is sufficient to scare the jeepers out of you.

Ghost stories are also most interesting when they reflect the internal tumult of their characters. Uncertainty, fear, depression, sadness. Ghosts appear often to people who have lost a dear one recently not only because only dead people turn into ghosts and haunt their near and dear ones, but because people are at their most vulnerable at those times. Hospitals are good places to haunt, and so are places where suicides and other particularly dissatisfying forms of expiration have taken place.

But what now in a world that doesn't believe in these forces anymore, where beliefs in such powers is considered 'superstitious'? How do convince the 'savvy' readers that there's something scary out there. By being a miser with words. Using the fewest words do describe the most, letting the readers' imagination fill the rest. By merely implying that there's something strange and otherworldly happening, and it could happen to you too. It's not the ghosts people are scared of, it's the idea that ghosts exist. Didn't Roald Dahl famously claim that the best ghost stories are those that don't have ghosts in them, after all?