"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 floats in the air."
Then you'll use infrared sensor to detect the invisible fire.
"Good idea, but the invisible fire is heatless."
You'll spray-paint the dragon and make her visible.
"Good idea, except 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. What I'm asking you to do comes down to believing, in the absence of evidence, on my say-so.
The bolded portion of this quote from Carl Sagan's "The Demon-Haunted World" is what I am interested in debating. My position is as follows:
1. There is no difference, the dragon might as well not exist.
2. The claim is worthless.
The following is why I think the dragon exists:
1. Clouds exist.
2. Anything that exists must have been created.
3. Clouds exist.
4. This dragon is the only thing that can create clouds. There is no other way.
5. Therefore, this dragon must exist.
Sure I do not have any evidence that clouds can only be made by this dragon, but you cannot disprove my claim. To disprove my claim you would have to provide another way that clouds are made. Since you cannot my claim is perfectly rationale. I have no physical evidence that this dragon exists but I have faith and that is good enough a reason for billions of people to believe in something, so it is good enough for me and should be good enough for you.
Oh and if you do find another way in which clouds are made, say threw science or something, then I was mistaken. It isn't clouds that this dragon makes but stars. If you find another way in which stars are made then... so on and so forth until science has explained everything in all universes. Once that happens then I suppose I was wrong about the dragon.
Don't get hung up on the fact that a dragon must have mass to be a dragon, or fire must have heat to be fire. That really is missing the point.