So you have the means to travel through time and space, but why do it? Why go through all of the risks involved such as time paradoxes and other potential problems that haven’t been answered yet? Once again I will refer to various anime to give the answers.
Steins;Gate and Dragon Ball Z
One of the best reasons to take the plunge and travel through time is because this is your last and only option. In Steins;Gate, things get out of hand as the Future Gadget Laboratory is raided by SERN. Something terrible happens and Okabe is left with no choice but to try to use a newly created machine that will send him back in time so he might try to change what happened. As a rule of thumb, it seems that even if you are the first potential time traveler in history, and the world is facing an apocalyptic situation, than go ahead, because what could be worse than the apocalypse.
Dragon Ball Z also follows this idea. The future from which Trunks arrives from in the Cell Saga is already living under apocalyptic conditions. Two androids of incredible power ravage the world nearly unopposed, causing destruction and death in their wake. So Trunks goes back to past to warn everyone ahead of time. The strange thing is that Trunks isn’t able to change his own timeline, but is only able to help the timeline he arrives at in the past. As far as any other time travel fiction is concerned, Dragon Ball Z is an oddity from than norm.
The Melancholy of Haruhi Suzumiya
Now, there are times when unbeknownst to you, time travel is a necessity. Why? Because someone going back in time is the reason things are the way they happen to be in the present. To go back in time to preserve the events leading to the present is a perfectly good reason for time travel (But a major headache if you think about it too long).
In The Melancholy of Haruhi Suzumiya, there is the character, Mikuru Asahina, who is a time traveler sent back from the future to keep an eye on events surrounding Haruhi. Occasionally, Kyon, the main character, also meets with an older Mikuru, who comes from further in the future. During the anime and movie, it is interesting to see that for Kyon, going back in time is almost a fated event. Kyon’s actions that effect the past are something that have already happened.
Kyon: “Hey Nagato, Asahina-san is really a time traveler right?”
Kyon: “If that’s the case, I feel a contradiction regarding the process of time travel. ”
Izumi: “Your point being…”
Kyon: “Before, Asahina-san said there was no continuity between past and future. But in the end, I wound up going back in time three years and gave Haruhi superfluous information… and there’s the possibily that this information caused Haruhi to come to North High to look for non-humans in the first place.”
“In other words, there is some connection between the past and future. Doesn’t this contradict what Asahina-san told me?”
Nagato: “As there is no set conclusion to the paradox theory, there is no way to prove that there is no paradox.”
Kyon: “You might consider that an adequate explanation…”
Nagato: “Soon you’ll understand.”
I understand, maybe, but if I think about it too long… my head hurts.
Sometimes going back in time is merely what was meant to happen. If Kyon didn’t go back into the past… well Haruhi may not have ever met Kyon in the first place. I won’t go into too many details as to everything that happens to avoid spoilers.
And there you have it, two really good reasons to travel back in time. It may be a little selfish to risk the destruction of the universe on a time paradox, but an apocalyptic event is something nearly anyone would want to avoid.
Also, without knowing it, traveling back in time and effecting something in the past may be something that needs to happen (in fact it already has happened–headache inducing).