Never seen one, nor do I believe in any.
I genuinely do not believe in anything supernatural, aside from a very narrow amount of basic religious matters.
I don't think there's anything evil out there in the world, outside of the evil we create ourselves. We might be creatures of free will, but that free will is a double-edged sword. Looking at history and how often we've used legends to shoo away shameful things from the past, I'd say ghosts and monsters are, on a purely psychological level, the excuses we make for our own past evils, or for our own anxieties. There's also archaeological evidence, going as far back as the Neolithic of the Fertile Crescent, that shows people were superstitious about resettling habitation sites that already had ruins of past buildings. "Unknown ruins ? Abandoned house/fortress/etc ? Must be haunted !" is an age-old human gut reaction, a fight-or-flight response present in all humans to varying degrees.
Concerning natural triggers for ghosts and feelings of being haunted, look up "infrasound", "sleep paralysis" and some interesting non-fiction on how our minds can easily trick us into thinking we saw or heard something. I can guarantee you that people who want to believe they saw something spooky will see something spooky, even if they saw the same allegedly spooky thing with someone who doesn't jump to conclusions right away, and that latter person saw or heard nothing.
I feel the same about the whole UFO/saucer craze of decades passed (now seemingly something of a spent fad): If you're convinced UFOs are "flying saucers" or other alien spacecraft, visiting Earth (out of boredom ?), they're already IFOs, since you've identified them as something you want them to be. On a sidenote, even Ken Arnold, with whom the whole UFO craze indirectly started in the 1940s, never called them "flying saucers", nor did he claim they looked like that. With the amount of supposed alien sightings that sound like they came out of a UFO popculture manual in terms of their tropes and clichés, I think it's safe to say popculture aliens, UFOs and "alien abductions" are the work of the human mind as much as fairytale monsters were in centuries past. The abduction narrative is also something that's common to fairytales and legends, making things even more suspicious on a psychological level.
While werewolves and fairies have given way to greys and little green men in the popular imagination, ghosts are more timeless bugbears precisely because they're a lot more abstract. They could fit any period, really. (I've always grinned at the holographic "ghosts" from System Shock II.) You can fit them into any spooky or tragic narrative, tweak their generic appearance in whichever way you like. Ghosts haunting castles are passé ? Make them haunt an underground parking garage or something ! Tada !
There is an excellent old Slovak saying about the mind playing tricks on us: Čo sa babe chcelo, to sa babe snilo... ("What the old woman wished for, the old woman dreamt about...")
As a Thief and Dark Mod fan, I'm confident that whenever I hear strange things go bump in the night, it's not ghosts or monsters. It's some bloody hooded taffer sneaking around my house, blackjack and all !
Edited by Petike the Taffer, 30 October 2018 - 04:29 AM.