Temporal Paradoxes in Anime and Manga.
Grandfather Paradoxes
- Date A Live: Origami experiences one when she realizes that she's the spirit that killed her parents, as she went back in time to kill the spirit that did so, but unintentionally killed them in front of her younger self in the process of facing a different spirit.
- Dragon Ball Z follows the multiverse approach, as explained in the manual by Akira Toriyama — each timeline exists in a separate dimension, so if you go to the past and change something, nothing will happen when you go back to "your" future. It makes things a little more poignant for Future Trunks, who travels back in time knowing that changing the past won't affect his Bad Future, but still idealistic enough to believe he can help some other universe with his future knowledge. Toriyama's explanations suggest three alternative timelines, but fans have extrapolated a couple more to make sense of things:
- Line 1: The timeline we see in the anime and manga. This timeline's Cell is killed in larval form so that he doesn't terrorize that timeline, and the Trunks who grows up in that timeline is quite different from the one from the Bad Future who visits early on.
- Line 2: The native timeline of Future Trunks. That Trunks has no reason to think his actions in Line 1 will affect Line 2, but he does get strong enough from everything that happens in Line 1 that he can easily defeat the Androids and Cell once he returns to Line 2.
- Line 3: The native timeline of Future Cell, who kills that timeline's Trunks, steals his time machine, and becomes the Big Bad of the saga in Line 1. Interestingly, Future Cell and Future Trunks originate in different timelines but arrive in the same one.
- Line 4: Extrapolated by fans noticing that in Line 3, Cell kills Trunks after he returns from the past. But this isn't the Trunks from Line 2, who survives to defeat that timeline's Androids, so the Trunks Cell killed must be a different Trunks, and this is the timeline he went to. The commonly accepted theory (suggested by the Daizenshuu guidebooks) is that Line 4 is exactly the same as Line 1 up until the point of Cell's discovery, at which point the androids are summarily defeated before Cell could absorb them. Most likely, Krillin never destroyed Bulma's deactivation switch in this timeline, which allowed them to be easily defeated (and then Trunks could take it back to Line 3 to defeat those androids).
- Line 5: Also extrapolated by fans, in the sense that Line 2 Cell would have visited this timeline had Line 2 Trunks not returned from Line 1 so ripped that he could defeat Cell before he could travel back in time. But things aren't great for this timeline — Future Trunks has no idea about Cell until he encounters Future Cell in the past, and with no Future Cell, nobody has any reason kill that timeline's larval Cell before he becomes a threat, nor will the Trunks who visits Line 5 be strong enough to defeat his home timeline's Cell when he returns. There's a reason we're looking at Line 1.
- Haruhi Suzumiya: Every instance of time travel in the stories (and there are many) invariably generates paradoxes like these. Characters go back in time to save themselves, information comes out of nowhere, etc., etc. Of course, no explanation is ever given in the books.
- Your Name gets into one of these once the time travel aspect is revealed. Taki and Mitsuha have spent the last few weeks randomly swapping bodies, until it abruptly stops happening. Taki tries to find Mitsuha, only to discover that they're three years out of synch — he's in 2016 while she died in 2013 when her town was destroyed by a fragmenting meteor. Armed with this knowledge, Taki tries to force one more mind-swap. He succeeds and, working with Mitsuha and her friends, they ultimately manage to evacuate the town to safety, saving all. This has absolutely no effect on Taki or any of the other events of the movie, except for the ending, where a now-living Mitsuha finally meets Taki face-to-face in 2022.
Ontological Paradoxes
- Dragon Ball Z: In Dragon Ball Z: Bardock - The Father of Goku, Bardock attempts to stop Freeza from destroying Planet Vegeta to prevent the creation of a Super Saiyan. He fails. In the Episode of Bardock spinoff it turns out that Bardock wasn't killed in the explosion but was sent back in time to before the Saiyans discovered Planet Plant. He fights Chilled, Freeza's ancestor, and during the fight he becomes a Super Saiyan. This means that Bardock is the Super Saiyan of legend, and that Chilled was the one who passed the legend down to King Cold and Freeza. That in turn means that Freeza destroyed Planet Vegeta because Bardock became a Super Saiyan when he fought Chilled.
- What's more is that Freeza ordered Dodoria to kill Bardock specifically because he feared Bardock may become a Super Saiyan...
- Of course, this is all meant as a What If? story, and considering how time travel normally works in the series, Bardock may have simply created a separate Alternate Timeline where all of this is what happened instead.
- In The Disappearance of Haruhi Suzumiya, while traveling in the past Kyon is stabbed by Ryoko Asakura. As he lies bleeding out on the ground, what appears to be a Kyon from the future comes with a Yuki and a Mikuru also from the future and rescues him. So, basically, Kyon only lived because he lived long enough to go and come back to save himself. He lived because he lived. My head hurts...
- Don't forget the information paradox with the knowledge of Mikuru's mole. Kyon didn't know Mikuru had the star-shaped mole until future!Mikuru showed it to him. Mikuru herself didn't know until Kyon told her about it. When future!Mikuru realizes this, she is understandably upset, thinking she messed something up.
- Or the "Endless Eight" story arc, which finds the central characters reliving the same eight day cycle 15,498 times (quite unbeknownst to anyone but Yuki). They finally break the cycle when Kyon suggests a suitable ending to their summer vacation to Haruhi.
- In INVADERS of the ROKUJYOUMA!?, Theia gets the school Drama club to do a play she wrote about an ancient legend on her homeworld. Kotarou ends up with the starring role of the Blue Knight. This involves not only memorizing his lines, but actual training in ancient sword styles. When he ends up on said homeworld millennia ago, He takes on the Blue Knight's role for real in an attempt to avoid a paradox, using the same skills and even lines he learned for the play.
- And again, Kiriha takes Kotarou out on a date like the one she went with a boy she fell in love with ten years ago. Later, Kotarou ends up ten years in the past(on his way back from the previous adventure) and meets a girl he is unaware is actually a young Kiriha. He ends up taking her on the date Kiraha would revisit years later because that's the closest thing to a date he's ever been on.
- The sundial watch in Humanity Has Declined exists in a cycle of being stolen and given away between "Grandfather" and "Watashi", with no original in sight. Particularly noticeable since the other paradoxes all turned into dogs.
- Transformers: Armada, in the "Drift" episode. Starscream is blasted with the Requiem Blaster, then Highwire somehow apparently warps the kids back in time, but in an Alternate Universe, where both the Autobots and Decepticons are imprisoned and slowly being digested within Unicron. Before he expires, Hot Shot reveals that the Minicons are actually Unicron's cells, and the Transformers were being used by them. Then the kids travel further back in time to when the Minicons were created. Here they tell them to escape from Cybertron, eventually resulting in them coming to Earth and all subsequent events in the story. Then, back in the present, Perceptor stops Thrust from blasting Starscream. Therefore, the kids had to go back in time to trigger the sequence of events that led them to Cybertron and ultimately the time travel event itself.
- Tsubasa -RESERVoir CHRoNiCLE- has several such paradoxes. One of the most noticeable is Real!Syaoran, who is a living, breathing time paradox, what with being he's the son of his own clone. It's implied that the timestream was desperately trying to hold itself together, resulting in a few Stable Time Loops to patch up other paradoxes, resulting in Real!Syaoran's existence. When everything is sorted out in the end and the multiverse is repaired, Clone!Syaoran and Clone!Sakura are RetGonned from existence, and Real!Syaoran almost ceases to exist because if his clone never existed, then neither could he, and he only ever really existed in the first place because he went and broke causality. The same thing goes for Watanuki, who only started existing to fill out a hole that Syaoran went and made in the multiverse by time-traveling. Now they've both got to pay for the repairs, so Real!Syaoran exchanges his ability to stay in one world for very long for his right to continue existing, while Watanuki instead trades his ability to go anywhere ever except Yuuko's shop.
