But lots of people believe lots of clearly false things, right? Lots of people claim they can feel EMF radiation from cell towers. A surprisingly large number of people believe that a witch has stolen their penis.
If 50 million Americans claimed they had seen a unicorn and the best picture we had of a unicorn was a grainy black and white from 100 years ago, I would reach the same conclusion: those people are mistaken about their explanation for the experience they had.
50 million people claiming they’ve seen ghosts demands an explanation, but the existence of ghosts is not the only or best explanation for those claims. Furthermore, it’s at odds with the other evidence we have (that whatever they’re claiming to ‘see’ cannot be photographed).
We can disprove plenty of specific concepts of ‘god’. We can disprove the god that brings the sun across the sky in his magic chariot, because we can see that that’s not how the sun gets across the sky. If one of god’s attributes is ‘typically answering prayers to heal the sick’, we can disprove that by seeing whether praying for someone makes any difference in how they heal.
‘God’ is a lot of different things, and many of them are unfalsifiable by design. It doesn’t follow from that that anything anyone has ever called ‘god’ is unfalsifiable.
To say it again: ‘ghost’ is many ideas. Some are unfalsifiable, some are not. I am claiming that the specific falsifiable idea of ‘ghost’ that I describe in the OP has been falsified.
But that isn’t true. I don’t need to check behind the sofa before I say “there are no extant thylacines”.
My point here is not that a ghost is like a thylacine in every relevant respect, it’s that we can exclude the possibility of a thing’s existence without directly observing every space the thing could fit.
The prevalence of cameras approximates a global search for ghosts that emit or reflect light.
Today, approximately everywhere that a human claims to see a ghost, there is a camera within arms reach. In many locations where humans have historically claimed to see ghosts (e.g. Starfire’s railroad tracks), there are now cameras recording all the time, in reasonably high resolution, often redundantly from multiple angles. Pictures and video can be easily shared by individuals.
The omnipresence of cameras is literally used by law enforcement to search for suspects and fugitives.
Every empirical finding published today is reported with a P-value, indicating how likely it would be to make the reported observations assuming that the hypothesis being tested is false.
Because empirical facts are always uncertain, and ‘proof to a practical certainty’ is the best we can do.
Strawman. I’ve never made this argument or any argument like it.
Logically, yes. But the odds are very, very, very low.
We ‘know’ it as well as we can know many of the mundane facts that we regularly accept.
Ghosts aren’t logically impossible, they are empirically inconsistent with the evidence.
What do you mean by “undetectable”? I would count seeing something with ones eyes as ‘detecting’ that thing. A thing that emits or reflects light can be ‘detected’ by measuring that light. A thing that changes the temperature of a volume of air can be ‘detected’ by measuring that change in temperature.
If people are ‘seeing’ ghosts, like literally using their eyeballs to process incoming light emitted or reflected by a ghost, they are detectable.
Lots of people believe that there are pictures of ghosts! Ergo, they believe ghosts can be photographed, ergo there are times and places where ghosts can be ‘detected’ by cameras. If we increase the incidence of there being a camera present in those times and places, we would expect more and better pictures of those supposedly detectable-by-cameras things.
This isn’t true (10 seconds of Google Scholar search turned up “Has the Amyloid Cascade Hypothesis for Alzheimer’s Disease been Proved?”).
But it also isn’t the basis for the objection to my claim. It’s not that I claim to know something, it’s that I claim to know this specific thing. Multiple people in this thread (including you) have trotted out plenty of other scientific claims (luminiferous ether, animal communication, ball lighting, phrenology, miasma), and no one has objected to them.
This is word games.
I still wouldn’t put it this way – priors are subjective, but probability is just math.
But this touches on a tangential point I think I mentioned earlier but can’t find at the moment: If knowledge is a matter of certainty, then it’s possible that two people with very different priors could justifiably claim to ‘know’ incompatible claims. At least one of them would have to be mistaken about her knowledge, but they wouldn’t necessarily be unreasonable to claim to know it.
Anyway, I don’t think that’s the case here. I don’t think our priors are so different that we should be interpreting the evidence in radically different ways. Everyone in this conversation should be able to agree with high confidence with claims like, “Ghosts cannot be captured on camera”.
OK, say ‘confidence’ or ‘certainty’. Does this distinction make a difference?
This is why it matters that probability is no subjective, even if priors are. No matter the subjective difference in our confidence/certainty in statements X and Y, the conjunction (X and Y) must be less likely.
It’s a mathematical truth; it isn’t subjective at all.