Say you go back in time and run over a cat on accident. That sets off a chain of events, and so on. Now, if you go back in time and kill yourself before you run the cat over but somebody sees you do this, it sets off another chain (though you arguably "fixed" the problem).


Naw, what I'm saying is let's say a cat jumps in front of your car. Two timelines exist already(and presumably always existed since the Big Bang). One in which you hit the cat and one in which you don't. You will go down one of those timelines and continue on, just as if you chose the right fork in a road. If you go back in time, you can choose the left fork, but you haven't changed anything but your own direction. The road never changed.

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chicken butt