I was looking for a test that a person might conduct to decide if the group that sees something really sees it, or is seeing things. Let me give you a concrete "what if" :
You and the rest of your ten man detail are on maneuvers in an Afghani desert when an explosion kills three of your squad, and leaves you blind and limping. Two three-man details go in opposite directions in search of water.
They each return to you claiming that they have seen water in the distance, are planning to go to the water, and will help you get there with them inasmuch as you are not expected to survive long enough for them to return with water for you.
Both groups swear that they have seen water, but it's very hot out, they're dehydrated, and you realize that one or both groups might be seeing things - a mirage. Which will you follow, and how can you decide? In other words, is there a way to decide when a group of people claim to see something whether they actually do?
The problem was designed to force you to choose which group to follow. Let's say for simplicity's sake that one group has actually found water, and the other saw a mirage. How can you tell which is which?That's a tough one.
I think I would ask(or order) that they dig a shallow pit, drag one of the bodies up next to it and cover it with sand...dig up a couple belts, a knife, and something plastic if possible, and leave me one clip & pistol...take the shortest route available to support, and then send back evac if it is possible. "don't worry - I'll be just fine boys" - now move it!"
Here's my solution:
You interview the soldiers. With one group, all three report, for example, an oasis about 500 ft in diameter about three miles away, with two palms on the right side, three on the left, a blue-green color to the water, and a sand dune with the profile resembling George Washington behind it.
The members of the other detail each gives you a different report, with wildly varying descriptions. And when they are questioned a second time, they not only continue to contradict one another, but they begin to contradicting themselves.
So now who saw water and who saw a mirage?
Incidentally, this is the same technique the police use when interviewing suspects. They interview them separately and compare stories to judge if their stories are based on experience or fantasy.
Ask Christians about the god they see some time, and you can solve this mystery for yourself as well.
I used to ask myself, "How can I tell if my god blindness is like color blindness blindness to something that is really there - or if the claims of seeing a god were like the paranoid's claims seeing danger that isnt there?" The answer is the same:
The color blind know that normally sighted people are actually seeing something that they are not, because of their ability to identify colors consistently, and to agree among themselves about what they see, such as socks not matching. Not surprisingly, the two groups don't argue or fight about reality.
The paranoids, however, are different. They seldom agree, even with themselves, coming up with ad hoc argument after argument for why the danger is real, each contradicting the last one, with no two paranoids having the same version of their delusion, and most frustrated with and angry at those who "pretend not to see the obvious."
Unlike the color sighted, the paranoid have to plead emotionally and passionately to be believed. Which group do the religious most resemble? Many angrily chide the rest of us for disagreeing, often using the same emotionally charged pleading as the paranoids.
Furthermore, each describes a different god, contradicting not just one another, but themselves from telling to retelling. That's how I know that the god visions are in their heads.