Do you believe ghosts are possible? If not, what do you think people's experiences of ghosts actually are?

No. It would be neat, but there is no evidence for it. I say this as someone who used to believe and made a website in ~2001 about haunted locations, our visits to some, etc.

As for what people see, it really depends. Pareidolia is a thing, so humans, I think, often see things not exactly as they are, especially if it's something in the vision for a very brief amount of time.

Religion-fuelled psychosis in already mentally unstable religious people.

I want to believe in ghosts, because of the broader implication that there is something beyond this life, but I have not seen any credible evidence of ghosts. As for people's ghostly experiences, I think that the vast majority of it is obvious bullshit that people invent to make their lives seem more interesting than they really are.

I've been to lots of allegedly haunted places; graveyards, houses, prisons, asylums, castles, battlefields, etc, and never once saw or experienced anything ghostly or even ghost adjacent. Without fail, there has always been at least one believer who told me that I need to believe in ghosts in order to see them, which is the dumbest thing I have ever heard. They also seem to believe, for reasons that escape me, that ghosts speak and understand modern English, regardless of what era or region the ghosts are supposed to be from. I just can't wrap my head around the logic that once you die, you magically know all languages, past and future.

If someone tells me they've seen a ghost, I'll take them at their word. I won't call them a liar, because maybe they did see something, and "ghost" is just the best explanation they have. But in order for me to believe it, I need more than eyewitness testimony, and in this digital age of easily accessible high quality special effects, a shaky low resolution out-of-focus 5 second video of "orbs" just won't cut it.

I hate sounding like such a downer, because I know a lot of people truly believe in ghosts, but the paranormal community is just so full of hucksters and suckers that it's exhausting to sift through all the blatantly fake crap in search of some truly compelling evidence.

I think ghosts, if anything, might just be people who are extremely sensitive to changes in the natural electromagnetic field seeing things. Such sensitivities have been known to cause visual or aural hallucinations, and many "haunted" locations do have uncommon magnetic field anomalies. Similar to how sightings of various entities more than likely stem from hallucinations caused by sleep paralysis.

There is also just paradolia in general; seeing faces in random noise, or hearing voices in random noise. This is basically what EVPs and "ghosts" in photographs are.

Lies, hysteria and confusion, in that order.

As a little kid I thought our house was haunted numerous times because of hearing weird noises and whatnot that I couldn't identify at night and just not having the life experience to account for it. Not once have I experienced anything like that since I was teenaged and up. I think adults experiencing things like that just never grew all the way out of that stage.

Once you learn what all the weird sounds are that you hear at night other people's ghost stories all start to make a lot more sense.

Every single personal story about ghosts I've heard can be explained with science.

I'm open to being wrong about it as I am with most things, but scientifically there doesn't appear to be any water held up in that one.

Ive had multiple experiences, so yes I 100% do. We used to sit at our living room and hear footsteps coming down the stairs but never anyone there. Then one time I saw a little girl in pink run from the stairs to the laundry room. Nobody was there and our kid was upstairs sleeping. Wife saw it too.

If ghosts were real, they would already have been studied and commodified in some way.

I was looking for a clip from an audio book I listened to a long time ago but search engines suck these days so I'll try to explain it from memory.

Imagine two of our ancestors in the jungle. They hear a rustling in the bushes or see some movement in the trees. One ancestor's brain recognizes the shape of a leopard and flees. The other ancestor assumes it's just the wind or a trick of the light.

If the first ancestor was right, the second ancestor may have been attacked by the predator and not survived that moment. If the second ancestor was right, barring extreme circumstances, both are likely to have survived that moment. Type 1 errors (false positives, the sign of predator is perceived when one isn't there) are less detrimental to survival than type 2 errors (false negatives, the sign of a predator is not recognized when one is there).

Humans are extremely accomplished pattern recognition machines. As a creature that evolved and had to survive in dangerous environments, it has been a benefit to error on the side of false positives when perceiving threats and making split second, life or death decisions.

pareidolia

This has also led us to presume agency, that we perceive a being like a predator or another person, as that would again be beneficial to presume incorrectly than incorrectly not perceive.

Many paranormal experiences are perceived as dangers or at least trigger a similar fear response. We're recognizing patterns that may or may not be there and, as we have evolved to be better safe than sorry, we attribute that recognition to mean there is something, likely a being of some sort, causing that pattern.

This even extends to the random occurrences of everyday life. Coincidences become good luck or act of a benevolent or malevolent spirit or God. Someone keeps having bad things happen to them? Someone must have curses them. Someone is in a hurry, needs to stop by the shop to get a gift or something, and just as they drive by a car leaves a parking spot right at the front of the store - God be praised, he's looking to for me today!

Dimensions bleeding into other dimensions.

No, there’s lots of reason people can experience things that aren’t there. It’s extremely common in fact. Full hallucinations aren’t even a sign of mental illness on their own, many people experience them. And then there’s stuff like mind altering substances, random events that your mind associates with a non-existent pattern (like the constellations), and other phenomena. None of which requires anything supernatural to be happening.

But I get it. Ghosts are kinda fun. Sometimes I like to pretend.

Probably hallucinations and something similar to delusional parasitosis, a little schizophrenia

I see things flicker in the corner of my eye too, but I don't attribute it immediately to "ghosts". Occam's razor is a ghosts' biggest enemy.

I've experienced multiple paranormal events in my life that I, or my family, were never able to explain. However I don't think they were "ghosts" in a sense that they are spirits of the dead walking around my house. My best guess is that paranormal activity is just a phenomenon that occurs when thin spots in the space/time fabric show up and cause multiple realties to exist in the same spot simultaneously. So what you are seeing is other people, or even yourself, in another reality or time. Then similar to a bad TV signal you sometimes get a crystal clear picture with sound, and other times it's all broken up and you have to interpret it through the static.

How do these things spots show up? No clue. But in a universe where black holes, and other similar things, are possible it is a lot more believable to me than ghosts or demons being the culprit.

Too many drugs