The op EXPICITLY states that the universe(solar system) is the peak limit to the “real world”, therefore outside of the universe can only refer to things literally outside the real world. Which only leaves the afterlife or the layers above it, as again the real world caps out at the universe,
furthermore in the context of the literal exact same scene “outside of the universe” is literally verbatim portrayed to be the afterlife:
I don't get this counter. The OP also elaborates how things outside the solar system are equivalent to things outside the universe, so I assume the intention was of arguing that going beyond the solar system won't just make the solar system fictional.
“As it had said, "If someone could peer into the afterlife and return from there、they could prove this world is fictional”
This is just another example of fiction being used metaphorically.
The reason they say that afterlife's existence proves that the world is "fictional" is quite clearly stated:
“If only humans can observe the world, then when humans are gone, the world will cease to exist. But if the same person that died can come back to life, that means that someone is controlling this world. Which means it isn’t real,” Yoshie said, and then rubbed her temples like she had a headache.
Afterlife's existence means death inside the world isn't real, and characters coming back implies someone is controlling it from outside, meaning the world isn't real but has an illusory meaning. Never once is it stated that Afterlife's existence proves the world is fictional because afterlife sees the world as fiction.
They even directly say that death(literally just a concept) inside that world is fictional:
“If he doesn’t mean destruction in the true sense, then it makes the question I had more plausible... My question, you see, is about the fictional nature of death in this world.” From her expression, Yuko could tell that this wasn’t just one of her usual fancy speeches. There was a deeper meaning. If she was bringing the subject up now, no matter how strange it may seem, it must have had something to do with what they were discussing. “The fictional... nature of death? Do you mean death isn’t real?” Yuko asked. Yoshie nodded.
“W-What...? So death isn’t real, and other worlds exist? I don’t understand at all.” Yoshie put her finger on her chin in thought, and then tried framing it another way. “I’m talking about the afterlife. What if the things we call heaven and hell are real? And then the world we live in now is a lie. Maybe it doesn’t matter if you live or die. The technology to travel through time, as well as the existence of gods from the outer universe hint at something... What if all life in this world was fictional? That would explain everything.’ “B-But we’re living! We’re suffering! Right now!” Yuko shouted. Yoshie nodded silently. “We’re each independent. We each have our own thoughts. So the world exists. But we can’t deny the possibility that the world is fictional. Unless we face death, as death...”
It is quite clear that the factor that is proving the worlds are "fictional" is death being illusory, not afterlife being a higher layer. And the logical progression being that coming back from death proves someone is controlling the universe.
“Many people have wondered if the world was fictional. For example, you may know that you exist, but perhaps the rest of the world is just an illusion. But there’s a clear response to that argument. The existence of other people. If you exist, then you must admit the existence of other people who think, and exist, as well. If you accept the death of others as equivalent to your own death, then you know that even if someone dies, the world remains.”
How does that quote prove this? It’s just Hiroshi recalling the different aspects of the cosmology he doesn’t say the afterlife is an alternate dimension he says that the verse (so far to his knowledge) consists of dimensions an afterlife, virtual dimensions, etc.
Because they are being treated as seperate worlds? If earth was fictional to afterlife it would have been part of it, not a seperate world. Not to mention, there isn't even actually a single statement calling afterlife transcendent even once. Death proving the world's fictionality has different context as shown above.
What makes you say that? For example why would the statement about the dreams within dreams be metaphorical.
Controlling the world from outside the solar system=seeing it as fiction apparently, so guess it would be a hierarchy of solar systems. Anyway, that dream hierarchy was literally a hypothetical one off thing that was never mentioned again in the next volume and not even ascertained whether it is even part of the Cosmology or not.
cus Hiroshi never was fictional to akuto though
Yet Akuto can create a low density story with him as a character and he can complete Akuto's story from inside this story.