Correct. Which is why I am not saying that claims that are indistinguishable from stuff that someone just made up are false. Really, even stuff that someone in fact just made up is not necessarily untrue. It is possible to make shit up and end up with the truth. But most claims that you could make up are false (for any claim A that you could make up, you could also make up at the very least the claim that not A, and at most one of those two can be true), which is why just making things up is not a reliable way to determine truth.
> Given that claims "indistinguishable from stuff someone just made up" could be true, one might think that there may be claims which, though are non-testable, are reliable for use.
"reliability of a claim" means the probability that the claim is true, based on what you know. The fact that some of the claims might be true does not mean that the probability of any particular claim being true is high.
> Also, when you say a claim is reliable, what is it reliable for?
It's not reliable _for_ anything, it is simply likely to be a correct description of reality.
> You may need to elaborate for me, because true claims can't potentially be shown to be false in principle.
Yes, they can, and that is the most important part of it that you have to wrap your head around.
The claim "water boils at 100 °C (at standard pressure ...)" is probably true, I suppose you would agree?
Here is an observation that could potentially be made that would count as falsification of the claim: Water in liquid form at 200 °C (at standard pressure ...).
Testability is not about actual demonstration, it is about potential demonstration. There has to be some demonstration that, if it were done, would be accepted as demonstrating that the claim is false.
The whole point is that for actually true claims, those demonstrations will never be actualized. But for actually false claims, they might, and often are. And that is how we weed out false claims, thus increasing the concentration of actually true claims in what we consider "state of the art human knowledge".
It is important to remember that "water boils at 100 °C" is not something we know for absolutely certain to be true. All attempts to falsify it so far have failed, that is all: All experiments so far have not produced any result that contradicts that claim. But for all we know, someone could demonstrate liquid water at 200 °C tomorrow (or water steam at 50 °C, or whatever--there are tons of demonstrations that would be accepted as falsification of that claim), and that would establish that this claim is false, after all.
> Assuming your saying "It is not warranted" because the claim "God exists" is not falsifiable, how has it been shown that the claim "God exists" is not a falsifiable claim?
What would you accept as falsification of the claim of the existence of the god that you believe in?
> Oh, so you agree that science relies upon the reliability of the senses and that the claim "our senses are reliable" is not falsifiable in principle?
All you are really saying here is "What if reality isn't real?" That is just a pointless objection. Whatever "ultimate reality" looks like, we still have to deal with the reality that we experience, and we most certainly experience what we experience, and the possibility that we might not be experiencing "ultimate reality" does not change that we are experiencing a reality, and that it is meaningful to make statements about that reality.
> Did you read it?
Yes, but it didn't seem like you changed anything of substance, in particular with regards to my criticism.
> Could you quote something from the second argument that treated "explainability as a property of X"?
The problem is that you are writing so massively ambiguous statements that it is very hard to nail down what you actually mean, and thus where exactly you treat explainability as a property of X. Even the first half of a sentence, "If X can't be explained", certainly sounds like "can't be explained" is a property of X. To avoid some of that ambiguity, I would very much prefer if you were to explicitly write down your argument completely avoiding "can be explained" or "has an explanation", instead using only "is known to humans" or "will be known to humans", and show that way that humans will at some point in time know everything.
And yes, I am aware that I am skipping a lot of stuff. I am getting the impression that we aren't getting anywhere with those due to way more fundamental misunderstanding, and I suspect a lot of it boils down to testability one way or another, so I think we are better off concentrating on that for now, instead of wasting a lot of time with going in circles.