Barry Taff, a noted parapsychologist (with a doctorate in psychophysiology and a minor in biochemical engineering), asked a pertinent question during a documentary about ghosts. He wondered whether, when we see a ghost, we are actually seeing something through our eyes and optic nerves – or whether something “directly stimulates the brain of the observer to impose an image on it. We don’t know.”
This is a great question. How indeed? Think about it. It’s not so easy to say or prove either way.
Taff also makes the point that ghosts are notoriously difficult to record with equipment, that when one is set up in one place, they will manifest in the next room over, etc. A filmmaker who worked on the documentary (I’m sorry I can’t remember which one) discussed a few cases – when the ghost was mentioned, the lights would turn off (and batteries would wear down in fifteen minutes instead of five hours). There was some footage of people discussing ghosts and the lights going off as they spoke and named the ghost.
These physical manifestations (another ghost pulled a window shade up and down) would seem to indicate something external to the mind. It still doesn’t answer the original question, whether we “see” ghosts with the eye or with the “inner eye” of the mind/brain.
Taff is a well-educated and very experienced parapsychologist. His question about through which sense/in which way we perceive ghosts is a good one. A note: to say we perceive it in the mind/brain doesn’t mean we are making it up – it just means that it somehow is sensed directly by the mind, not filtered by the eyes.
For more ghosts, fact or fiction, paperback or kindle e-book, see: https://www.amazon.com/Jan-Olandese/e/B071FK9L75