Never the Selves Shall Meet: Difference between revisions

{{examples}}

== [[Fanfic]] ==

* There was a ''[[My Little Pony: Friendship Is Magic|My Little Pony Friendship Is Magic]]'' fanfic which invelved Rainbow Dash travelling in time to set herself and Applejack up. Eventually, because of this, she, Applejack, and Twilight Sparkle are all jumping through time trying to make sure the right versions of themselves meet at the right time. It ends up with several dozen of each pony getting very confused. {{spoiler|And then [[It Got Worse|Scootaloo gets caught up too...]]}}

** Another fanfic, [[On A Cross And Arrow]], instead had dimensional travel replacing time travel. Twilight ended up sending the Mane Six into an alternate dimension where everyone is genderswapped verisons of themselves. She feared that if they met their alternate selves, they would explode or something. {{spoiler|Thankfully, this isn't the case in the slightest.}}

* The [[Star Wars Expanded Universe]] novel ''[[The Thrawn Trilogy|The Last Command]]'' by [[Timothy Zahn]] has a variant of this trope, involving [[Cloning Blues|clones]] instead of time travel. Clones grown near other set up "resonance effects" in the Force, which can drive them insane, and when Luke encounters his clone, he finds the experience incredibly off-putting: there's a buzzing hum in the Force that makes it hard to concentrate or think, making it difficult to fight the clone. This only seems to affect clones whose growth has been accelerated to an extreme degree—having them grow up in under a year, for instance—and Force-sensitive clones, since the clone army in the prequels (who take about 10 years to grow up) doesn't have any problems with this. Thrawn figures out away around it in the same novel, using lizards that can push away the Force to guarantee against the clone madness ''and'' dramatically decrease the time to grow them even further.

* One of the most important rules of [[Time Travel]] in [[Harry Potter]]? Don't be seen by yourself. You could panic and kill your past or future self. Notable for not really being a result of time travel so much as just being a duplicate. Though not spelled out explicitly in the books, this could have something to do with the existence of Polyjuice Potion—in most non-time-travel related situations where you notice a duplicate of yourself, it means someone's up to no good. As Harry's own experience with [[Time Travel]], which was the only one the readers were able to follow, turned out to be a [[Stable Time Loop]], the killing-your-past-self thing is unlikely to ever happen.

* The ''Time Scout'' series, which already presents time travel as potentially dangerous if you don't get the small details right, also avoids the meet-yourself problem by making it clear that you must never go back to a time when you already exist, either by having been born by then, or having previously visited via time travel; otherwise, since you can't be in two places at once, the "current" you who went back in time would simply wink out of existence the instant you arrived, and that's the end of you.

* In [[Connie Willis]]'s time-travel books, you simply ''can't'' go back to a time you've already visited. If you try it—or if your presence, for any reason, would cause a paradox of some sort—either the "net" (via which one time-travels) simply won't open, or it will deposit you slightly awry (in time and/or space) of your intended destination. Cosmic Censorship may be at work here: if you cause a paradox, then the next version of you is sent to a slightly different point (or the machine fails), repeat until there's no paradox.

* Subverted in ''[[The Hitchhiker's Guide to the Galaxy]]'' novel ''[[The Hitchhiker's Guide to the Galaxy/Life, The Universe And Everything|Life The Universe And Everything]]''; Ford Prefect and Arthur Dent arrive on Earth shortly before its destruction. Ford (who had, in the previous novel, explained to Arthur that history cannot be changed because [[Stable Time Loop|it all fits together like a jigsaw]]), warns Arthur against phoning to warn himself. Not because it'll do anything to the timestream, but just because it won't work. It had already been noted in ''The Restaurant at the End of the Universe'' that no matter how many times you visit the restaurant in the title, which you would always do in the universe's last half-hour or so, you are guaranteed to never run into yourself "because of the embarrassment this usually causes," despite this being impossible. How the people responsible for the restaurant's operation pull this off is not explained, but it is [[Lampshade Hanging|lampshaded]] magnificently along with other things about Milliway's by the Guide's repeated use of the phrase "This is, of course, impossible", and the restaurant's advertising slogan: "If you've done six impossible things today already, why not round it off with breakfast at Milliway's, the Restaurant at the End of the Unverse?".

* In ''The End of Eternity'', there is a natural law that keeps Reality from developing paradoxes, and thus keeps anyone from meeting his own past self. (The standard [[Grandfather Paradox]] is dismissed as the speculation of people who don't know about time travel.) So when the main character does see his own future self going about his time-travelling business, it's a sign that the normal way of things is beginning to fall apart.

* In [[The Book of the New Sun]], Severian feels absolutely certain that if he accidentally met himself while time traveling, one or both of them would go mad and kill the other.

** It seems, though, that they're more worried about changing their own history than a [[Time Crash]] resulting from simply being in the same place, since the same person being in the same place has happened so many times safely. If you interfere where you've ''already'' interfered, though, the [[Clock Roaches]] will getcha, as seen in the aforementioned DW episode, Father's Day.

** Like ''[[Back to The Future]]'', this winds up less of a cosmic rule and more of a guildeline to prevent paradoxes, since the timeline is ''very'' malleable (case in point, the time he {{spoiler|left a digital camera in the 1980s, which subsequently retconned his own son out of existance}}). But the protagonist is very [[Genre Savvy]] from the get-go.

* Through the mixed-up and convoluted story of ''[[Sonic the Hedgehog (2006 video game)||Sonic the Hedgehog 2006]]'', this essentially takes place. There probably isn't a time where there aren't at least two Sonics/Silvers/Shadows running around at the same time, just in different locations. For example, late in the game, Sonic, Silver, and (strangely) [[Sonic Rush Series|Blaze]] find themselves on a cliff, while Doctor Eggman's Egg Carrier crashes into the side of a mountain, leaving Sonic to believe Elise is dead. Silver then suggests Sonic goes back in time to rescue her. While this happening, {{spoiler|Sonic has already done so. He and Elise had already escaped the crash just as the carrier exploded.}}

== [[Web Comic]] ==

** Meeting and hanging around with yourself in Timeless Space is generally considered a bad idea, since it means you've managed to escape once before (and returned later), and most denizens of the place would ''kill'' to find out how you did it (or to prevent their enemies from finding it out). Having a normal twin is even more dangerous since people will just think you managed to escape even thouygh you never did.

* The ''[[Ben 10: Alien Force|Ben 10 Alien Force]]'' episode "Paradox" has Kevin's car turned into a literal rust bucket by a time monster that ages anything it touches. At the end of the episode, Paradox gives them a new (old?) car, with the warning that it will "explode like antimatter" if it comes into contact with anything else from 1976. However, earlier in the episode, Paradox spoke to an alternate universe version of himself without any ill effects - granted, they did not shake hands or anything, but still...<ref>[[Word of God]] is that Paradox was joking about Kevin's car.</ref>

* ''[[Bump in the Night]]'': Mr. Bumpy unwitingly insilted Squishington, who locked himself away as a result of it. Bumpy then went back in time to prevent that but failed. Then he went back ''again'' and failed ''again''. The three Bumpys then got an advice from Future Squishington and apologized to their friend. When Squishington asked the Bumpys why there were three of them, they disintegrated because they didn't agree on which ones had to leave.

* The ''[[Miraculous Ladybug]]'' episode "Timebreaker" defies it twice-over. Not only is Ladybug easily able to safely interact with - and form a team with - her past self, but Hawk Moth gets the smart idea to double his pawn's power by sending a second akuma to corrupt the past one, so ''they'' can also form a team. [[Fridge Brilliance]] kicks in here, as two Ladybugs were likely needed to purify two akumas.