Endwalker's story had me, but lost me. Ethical issues especially (spoilers)

[Rosenstrauch]

I thought the time travel already happening thing affects our current timeline, but what about the other where it wasn't possible due to WoL being dead? Does our going back in time in this specific timeline affect all other timelines where it wasn't even possible?

My head hurts.

Imagine it like a shoelace frayed on one end and held together by an aglet on the other. Though each strand branches off in its own direction, they gradually converge into a single thread the closer they are to the aglet.

Which is to say that our time in Elpis came to pass even though we weren't alive to go back there in the Eighth Era timeline, because we'd already done so in the New Dawn timeline, and the two share the same root of "every moment prior to the split". There is some degree of convolution to be had, of course: If you try to imagine them as wholly separate timelines, then they're codependent on each other. This is the kind of strangeness that happens when time travel keeps cropping up in a story.

If it makes you feel any better, the writers have probably had to sit down and figure all this out themselves, so any pain you might be feeling is something they've shared. Maybe.

[Veloran]

Imagine it like a shoelace frayed on one end and held together by an aglet on the other. Though each strand branches off in its own direction, they gradually converge into a single thread the closer they are to the aglet.

Which is to say that our time in Elpis came to pass even though we weren't alive to go back there in the Eighth Era timeline, because we'd already done so in the New Dawn timeline, and the two share the same root of "every moment prior to the split". There is some degree of convolution to be had, of course: If you try to imagine them as wholly separate timelines, then they're codependent on each other. This is the kind of strangeness that happens when time travel keeps cropping up in a story.

If it makes you feel any better, the writers have probably had to sit down and figure all this out themselves, so any pain you might be feeling is something they've shared. Maybe.

I'm not so sure that makes sense, given our timeline is causally dependent on G'raha's timeline, and in that timeline Venat would now be extremely confused about why she has a bunch of memories that no longer align with reality and are causally impossible.

[Rosenstrauch]

I'm not so sure that makes sense, given our timeline is causally dependent on G'raha's timeline, and in that timeline Venat would now be extremely confused about why she has a bunch of memories that no longer align with reality and are causally impossible.

Pardon my bluntness, but... no shit. It's time travel. Being causally impossible in our own reality is its single most defining feature.

[Veloran]

Pardon my bluntness, but... no shit. It's time travel. Being causally impossible in our own reality is its single most defining feature.

G'raha's parallel worlds time travel wasn't causally impossible. Until Endwalker anyway.

[Rosenstrauch]

G'raha's parallel worlds time travel wasn't causally impossible. Until Endwalker anyway.

It was impossible from the very beginning. You can't travel back in time, period. The laws governing reality don't allow it. But fiction asks us to accept that that it's possible to travel back in time. In order to understand a story in which time travel is possible, we must first suspend our disbelief.

So, G'raha traveled back in time. He did so with the intent to change the past. This is impossible. You can't change what happened in the past, because the past is a fixed series of events leading to the present. But we've already accepted, by virtue of suspension of disbelief, that time travel is possible, so any rules about being able to change the past are entirely arbitrary. As such, instead of kicking our heels in and decrying the impossibility of such events, we must ask what would happen if you attempted to change the past. If you can't, it's a causal loop. If you can, we run into the Grandfather Paradox—see below.

Anyways, G'raha then proceeded to change the way events unfolded in such a manner that his own future could not have happened. This is impossible because of the Grandfather Paradox—if an event in the past is dependent on an event in the future, then it can not negate that future without also negating itself. But since we've already accepted that time travel is possible, then as a consequence we have to accept that running into the Grandfather Paradox is an inevitability and come up with a solution. The solution the writers went with is Multiverse Theory. Thus G'raha and the changes he made to the timeline are able to exist, even though they are dependent upon events in the future that are no longer possible.

But that leaves the question of what happens to the future G'raha departed from. Since the events leading to it are no longer possible, its continued existence should no longer be possible as well. But once more the writers ask us to look to Multiverse Theory, and have decided that instead of negating its own existence, the future G'raha came from is instead on the same timeline as the one he saved, but as a separate branch from the one he saved. Their pasts are identical, but their futures are different.

Now, having established that, we come to our trip to Elpis. We have already accepted that traveling to the past is possible. We have also accepted that the continued existence of the Eighth Era future is possible. Now we have a time travel event dependent on the existence of G'raha having traveled in time. Easy enough to accept. While we're in the past, we attempt to change the past, inadvertently causing a causal loop instead. This causal loop is dependent upon G'raha's future to exist, as a direct consequence of G'raha having arrived from it. But G'raha's future is also one in which the events in Elpis must have come to pass, because that was also part of its own past—they're the same timeline, just ending on different branches.

Now I know what you're thinking: How can that be, if we died in G'raha's future before traveling to the past? And the answer is that we already did so from our own branch of the timeline. It's the exact same past, after all.

Now, this is utter bollocks. But every single thing about time travel is utter bollocks. If you're willing to suspend your disbelief to accept everything up to that point, what makes that last bit unacceptable? It's built entirely on things the writers have already established, and in no way contradicts them.

And just so we're clear: I have no interest in continuing this conversation further. Talking about time travel gives me a headache—and it's not because time travel itself is hard to understand. It really isn't. No, it's explaining it that's the painful part. Makes me feel like I—an American mutt who only understand English—am trying to speak Indonesian to Martians. All of this is a spectacular waste of everyone's time if we have a communication breakdown.

[Veloran]

Now, this is utter bollocks. But every single thing about time travel is utter bollocks. If you're willing to suspend your disbelief to accept everything up to that point, what makes that last bit unacceptable? It's built entirely on things the writers have already established, and in no way contradicts them.

That was quite a long post just to conclude with "it's dumb anyway, just accept it." But no, I won't, because the story never bothers to establish any internal logic suggesting a single derivatively-branching connected timeline, nor that the two are connected on the same branch, rather than, say, the concept of wholly parallel worlds. Your explanation is primarily your own headcanon and personal interpretation of how it works, for which I see limited - If any - evidence for within the narrative itself.

It's easy to say "time travel is bollocks", but the issue isn't with the time travel at all, it's with the writers not taking care to develop how these concepts function within the world.

[Rosenstrauch]

That was quite a long post just to conclude with "it's dumb anyway, just accept it.".

Hey, remember that thread about arguing in bad faith? Lesson learned: This is exactly why it exists.