Time travel has been a
sci-fi archetype for many moons now. Novels, movies, books, and video games have been devoted to this intriguing
fantasy.
But, sometimes, it just doesn't make any sense.
First of all, I'd like to give an example of when time travel (in this write-up, time travel means travel back into the past, not into the future) makes sense. The original Back to the Future movie is the best example. Michael J. McFly takes Doc's contraption back into the fifties, he obstructs the potential relationship between his mother and his father, and he needs to hook them up before he fades away. Now, this makes sense. Go back in time, screw things up which could injure the future, patch things up back together, and go back to the future (to a nicer house and car, in this case).
Of course, it does get a little ridiculous at times. ("My brother's head is gone!" I mean, wouldn't the three siblings fade at the same time? Actually, wouldn't the photo itself fade, since it was a photo of the McFly kids, and it wouldn't have been taken if they didn't exist.) But the basic premise of the plot holds, scientific limitations notwithstanding.*
But often it just doesn't work that way. Bill and Ted's Excellent Adventure is another Generation X classic. But the basic premise of the movie fails.
If the future is already a utopian society based on Wyld Stallyns, why does Rufus need to go back in time to ensure this?
If Bill and Ted were together for the rest of their lives and made some totally peace-making music, why did George Carlin go back in time to ensure this? That's like going back in time to ensure Abraham Lincoln gets elected president.
It happened in the past. You don't need to go back in time to ensure it.
The same goes for Sherman and Mr. Peabody of Peabody's Improbable History fame. Mr. Peabody and his boy, Sherman, would go back in time with the aid of the Wayback Machine, and there'd always be a problem. Some historical figure would have a fear of heights, or water, or there'd be too many Indians, or something. And Mr. Peabody would always rectify this problem.
But if the present is already as is, you don't need to go back in time to ensure it.
There's a new series on Cartoon Network called Time Squad. I admit I haven't seen it. But, from the commercials, it's fairly safe to assume it's a more modern take on Peabody's Improbable History. Eli Whitney invents a flesh-eating robot, Abe Lincoln is a prankster, uh-oh, call the Time Squad; they need to fix these things, post-haste! But, as said above, Lincoln sure as hell did become the 16th President of the United States. (There, now my w/u isn't entirely devoid of factual content.)
It happened. You don't need to go back in time to ensure it. (Have I said that already?)
Aside from these "let's fix the unbroken" cases, there are also the "that's far too convenient" cases. Perhaps the best example of this is Dragonball Z. Trunks goes back in time three years before he is born, tells Goku some androids are coming, and leaves. Eventually the rest of the Z Fighters learn that the androids are arriving, including Trunks's father, Vegita. Now, in Trunks's time, Vegita was unaware that there were any androids on the way, fell in love with Trunks's mother, Bulma, and knocked her up. But in this time, Vegita is prescient of the androids' arrival. His life revolves around the preparation for the battle, and yet he still manages to fall in love with Bulma, despite the fact that something like that would need to occur under very special conditions. And he had sex with her at the exact same time to the nanosecond that he did in the other time despite this drastic difference in lifestyle, because the present Trunks is the same as the future Trunks. But even worse than that ridiculous convenience is this: Trunks knew going back in time would endanger his birth. So why the hell didn't he go back after he was born, but for dramatic purposes! It certainly would have made a lot more sense if he did.
In conclusion, Time travel is a wonderful tool at a sci-fi creator's disposal to create a scintillating work that can inspire, challenge, and awe.
But PLEASE, people, just let it make some goddamned sense!