"A fire-breathing dragon lives in my garage"
Suppose I seriously make such an assertion to you. Surely you'd want to check it out, see for yourself. There have been innumerable stories of dragons over the centuries, but no real evidence. What an opportunity!
"Show me," you say. I lead you to my garage. You look inside and see a ladder, empty paint cans, an old tricycle--but no dragon.
"Where's the dragon?" you ask.
"Oh, she's right here," I reply, waving vaguely. "I neglected to mention that she's an invisible dragon."
You propose spreading flour on the floor of the garage to capture the dragon's footprints.
"Good idea," I say, "but this dragon floates in the air."
Then you'll use an infrared sensor to detect the invisible fire.
"Good idea, but the invisible fire is also heatless."
You'll spray-paint the dragon and make her visible.
"Good idea, but she's an incorporeal dragon and the paint won't stick."
And so on. I counter every physical test you propose with a special explanation of why it won't work.
Now, what's the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all? If there's no way to disprove my contention, no conceivable experiment that would count against it, what does it mean to say that my dragon exists?
Your inability to invalidate my hypothesis is not at all the same thing as proving it true. Claims that cannot be tested, assertions immune to disproof are veridically worthless, whatever value they may have in inspiring us or in exciting our sense of wonder.
The only thing you've really learned from my insistence that there's a dragon in my garage is that something funny is going on inside my head. You'd wonder, if no physical tests apply, what convinced me. The possibility that it was a dream or a hallucination would certainly enter your mind. Maybe I need help. At the least, maybe I've seriously underestimated human fallibility.
Imagine that, despite none of the tests being successful, you wish to be scrupulously open-minded. So you don't outright reject the notion that there's a fire-breathing dragon in my garage. You merely put it on hold. Present evidence is strongly against it, but if a new body of data emerge you're prepared to examine it and see if it convinces you.
Surely it's unfair of me to be offended at not being believed; or to criticize you for being stodgy and unimaginative-- merely because you rendered the Scottish verdict of "not proved."
I hadn't seen this piece before but I really like it. It's a very effective analogy and bears remarkable resemblance to my own religious views. I am not here to try to disprove the dragon's presence, but I'm certainly not convinced until it has been proven conclusively. As such, the dragon has thus far been very elusive indeed.