However, the more I think about it, the more I’m troubled by the presence of the compass. I love time travel, but the compass raises two very real paradoxes.
1. How Does It Jump?
Sawyer and Juliet theorized that because people were on the Zodiac during the first time jump, it is now jumping with them. But since they weren’t on it during subsequent jumps, but it was still with them, it must now be permanently jumping with them.
However, the compass Alpert gave Locke did not go with them during the first jump. However, when Richard gave it to John, Locke carried it with him through the next time jump. If it was fixed in time before that, this means that any object can be carried through any time jump. Either that, or it means the compass has special qualities like Desmond.
But if it’s true that the survivors can carry objects with them through time so long as they’re holding them, this could change a lot. Maybe during one jump, Sawyer hugs Claire and so the reason she vanished was that she was brought into the time jumps.
2. What Is The Compass’ Origin?
Alpert gave John the compass, saying that the next time they meet, he should give it back. Theoretically, this means Alpert will get the compass from John and John got the compass from Locke, but there is no origin point for the compass.
The compass would be locked in a never-ending loop, a Mobius strip of time. The compass has no origin outside of this loop, which begs the question: where did it come from?

I have no idea if either of these concerns are ones the writers will address, or if they’re my personal qualms about the realities of time travel. But much like the four-toed statue, I will be thinking about these paradoxes and questions until they’re answered.
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