Overview: Below is a quick account of how a new understanding of strong and weak inferences helped me defeat my irrational fear of ghosts.
A Personal Story:
When I was twenty-one, I moved into an old dorm room in Reading, England. Coming from Idaho, I was well aware that England, with its many castles, plagues, and beheadings, was where most ghosts preferred to live. We might have had some Native American or cowboy ghosts floating around, but they were probably way out in the desert, and they never seemed to bother anyone. My impression of England as ghost-central was firmly rooted in my 4th grade literary tastes, which was more or less limited to ghost stories and accounts of the paranormal. Most of these were set in giant British mansions with old cracked portraits and family cemeteries out back. Despite the distance, I was still afraid of ghosts most nights, but if there was one thing my 4th grade brain knew for sure, it was that England was ghost-central.
Even though I was older and supposedly tougher, my fourth grade brain re-emerged as I unpacked. Two weeks previously I had been placed in a bright, spacious dorm room, but the warden (is that what he was called?) asked me to relocate after a new freshman girl desperately requested to move. Her room was small and dark, and after two weeks, she determined that it was also haunted by an aggressive ghost. I met her as she was moving out, and she told me what happened. The issues were small at first. She would come back into the room to find that glasses and notebooks had been moved. Sometimes she would wake up in the middle of the night to see light bulbs burning that she was certain she had turned off. She was scared and slept uneasily. Late one night, she woke up and saw a large man standing at the foot of her bed. As she bolted up in panic, he disappeared. She requested to switch rooms the next morning, and somehow I got the nod.
Was I scared? Yes. I was scared. I don’t know why exactly. Ghosts don’t stab people or give us diseases. They don’t strangle us while we sleep. Apparently, they just casually mess with you, and occasionally wake you up and disappear. At worst, ghosts are pranksters. Even so, horror movies had taught me that some ghosts cross the line, and I might have a Beetlejuice, or worse, a Poltergeist (the first one) harassing me, killing me, or driving me insane. Of course I knew that I was being silly. Nevertheless, every time I came into the room, my senses were heightened. I did a full check of the room before sitting down, and every pinging pipe or random creak made me jump up and scan the room for something supernatural. It took me a long time to fall asleep, and I soon started waking up in the middle of the night. The first thought that came into my head was, “There’s a reason I’m awake. Something woke me up.” I would lie there for a minute or two before turning on the lights and completing a quick sweep – checking under the bed and in the closet in case the ghost was hiding (a classic ghost tactic).
Eventually, I knew I needed a way to exorcise my irrational fear. I was fortunate to be studying philosophy at the time and came across David Hume’s passage on miracles. After establishing the idea that we all share a baseline of “normal” experience, he argues that a miracle is anything that violates these laws (ghosts qualify). Hume notes that most of our experience of miracles comes second-hand, and that is a crucial fact to take into account:
“The plain consequence is (and it is a general maxim worthy of our attention), ‘That no testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous, than the fact, which it endeavours to establish….’ When anyone tells me, that he saw a dead man restored to life, I immediately consider with myself, whether it be more probable, that this person should either deceive or be deceived, or that the fact, which he relates, should really have happened. I weigh the one miracle against the other; and according to the superiority, which I discover, I pronounce my decision, and always reject the greater miracle. If the falsehood of his testimony would be more miraculous, than the event which he relates; then, and not till then, can he pretend to command my belief or opinion.”
[David Hume, An Enquiry Concerning Human Understanding, L. A. Selby Bigge, ed. (Oxford: Clarendon Press, 1902), pp. 114-16]
In other words: Was it more likely that there was a ghost (whose existence has never been reliably documented in this history of humanity) or that the frightened girl who had fled the room was mistaken or lying? To combat my fear, I kept this passage next to my bed and read it whenever I heard an inexplicable sound or woke up for no obvious reason. Again, was it more likely that the previous tenant was mistaken or possible deceiving me (to get a better room?), or was it more likely that there was an angry dead man subtly messing with me with little creaks and pings for no reason? In my experience, people around me sometimes lie and are sometimes mistaken, and I’ve never known a ghost.
It took me a few days to reroute my mental reactions. Every time I felt a pang of fear, I would take a deep breath and run through Hume’s basic thought process. My sleeping patterns quickly returned to normal. I wouldn’t have put it like this at the time, but Hume pointed out to me that I was consistently making and acting on a very weak inference. Why might an old building make odd noises? We could list a hundred good reasons before we get to ghosts. I was making one bad guess and letting it have a negative impact on my life.
Understanding inferences and how they work has cleaned many cobwebs from my understanding of the world, and it has helped me understand why I’ve done so many silly things, many of which only seem silly in the morning when ghosts are afraid to show themselves.