Future Carl informs Carl that the life he’s leading is the only one that’s insignificant enough that no paradox or disaster can possibly occur as a result of his time travel.
The only difference, apparently, is the major dressing used on a roast beef club sandwich at a place called Garalfalo’s.

Variants

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  1. “The Carl Paradox” by Steve Rasnic Tem, in Asimov’s Science Fiction, January 2014.
  2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Steve Rasnic Tem