I would suggest a robust definition of terms. What do we mean when we say ‘everything Battler sees is true’? Do we mean that everything he sees is as it seems, or merely that he sees it? Battler definitely hears about supernatural from other characters. What he hears may not be true, but it is true that he hears it.
We’re getting into philosophical territory here, but the witch started that when she brought up Hempel’s raven. Actually, @pik3rob, your observations on Shannon and Kanon made me think of another philosophical tool – the vacuous truth. A vacuous truth is true only because the antecedent is false.
Let me try to explain. Let’s say I make a modest claim – Ronove, I say, bake us some more cookies. I ate every cookie on my plate. Of course, Ronove has been watching me carefully. I did not eat a single cookie during our teatime. How can my claim be true?
Simple: Ronove’s cookies were still in the oven! If I wrote my claim as a condititional, you would see the trickery. If there are cookies on my plate, I ate them. But there are no cookies on my plate. The antecedent is false, so no matter the consequent, the conditional is true. But it’s true in an empty, vacuous way. An equally true statement would be if there are cookies on my plate, I did not eat them or I ate and did not eat the cookies on my plate.
Let’s make a more dramatic claim. Kanon is dead. The conditional: If there is a person named Kanon, that person is dead. But what if there is no person named Kanon? (This is what you’re stating, @pik3rob, with your blue truth: Shannon and Kanon aren’t the characters’ real names, so the red stating them as dead means nothing to their status.)
If I were Battler, and wanted to test the theory, I’d challenge the witch say ‘Kanon is alive’ in the same red. This would be a weakness in that and every red truth. If the antecedent is false, the conditional would be true, and thus could be said in red. We could comb over all the witch’s red truths again for hidden conditionals with false antecedents. In fact, doesn’t the witch issue a red truth like that in this very episode? This is my golden land. A world where magic that isn’t mine certainly cannot exist. But ‘golden land’ is an empty name (another philosophical term) and has no referent in the real world. Any claim we could make about it would be a vacuous truth. Would it not?
Of course, our host gave a bold truth in the episode 3 thread: Only one individual in this story may use the name Kanon. That is, of course, the Kanon we all know. I do not think this is inconsistent with supposing Kanon is an empty name. Only the Kanon we know can use the name Kanon. But using the name does not require it to have a referent. We use the name ‘witch’ and ‘demon,’ after all, and neither exist.