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Why do time-travel stories often have the characters “returning” to the future?

The possibility of time travel normally creates paradoxes. If you can travel into the past and kill your grandfather, how did you exist in the first place?

The usual way of dealing with the paradoxes of time travel in SciFi movies, books or TV series is to invent arbitrary rules (I think this is the Dr Who solution), move so quickly that the audience doesn't have time to think too much (Looper is a good example of this) or to just ignore the problem (Terminator 2).

Terminator 2 is typical of many treatments. The paradox is that the future that is avoided has already influenced the present: so how can the present not be self-referentially altered as a result of avoiding the future...

I don't think these problems detract from the great stories involving time travel. But, SciFi is a creative medium and I wondered whether versions or rules for time travel have been invented which do not suffer from the normal paradoxes?

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    Not sure exactly what you are asking here. Whenever a work of fiction deals with time travel it has to deal with it somehow...if they "invent arbitrary rules" then any "paradox" is no longer a paradox, as it no longer defies reasoning.
    – NominSim
    Nov 1, 2012 at 21:45
  • Guys I'm new here so I may be missing something, but the flagged question I'm supposed to be duplicating doesn't seem to overlap with my question that much. And the "arbitrary rules" issue is that inventing a rule without explaining why the rule exists is a very unsatisfactory plot device for anything. It's like saying there is no such thing as a paradox as a way of avoiding a paradox.
    – matt_black
    Nov 1, 2012 at 23:16
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    I would've closed this as something else, because there is no typical way to deal with time travel. Time travel in the sci-fi sense does not exist in real life, so all continuities have their own rules - they just happen to overlap and fall into a few categories in the "big picture" way. To answer your question using one of these "big pictures", here's just one solution: the branching universe hypothesis
    – Izkata
    Nov 1, 2012 at 23:19
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    My close reason was not that it was a duplicate...just rather vague and not really a question. Any work that offers an "explanation" for a potential paradox resolves the paradox...what "key paradoxes" are you talking about that are avoided?
    – NominSim
    Nov 1, 2012 at 23:34
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    Unfortunately the way the site is designed, it doesn't give everyones reasons for close votes...I didn't vote as a duplicate, but others did and that superceeded my VTC reason. I tried in my comments to say why I was VTCing....I apologize if I wasn't entirely clear
    – NominSim
    Nov 2, 2012 at 2:43

1 Answer 1


See the Novikov self-consistency principle. The novel Timemaster by Robert L. Forward is written using this principle.

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