Hi! Thank you for playing the game. I'll try to explain it without giving away too much of the story.
But for anyone who hasn't played the game yet: PLEASE STOP READING HERE AND GO PLAY CAUSALITY! It only takes about 5 minutes.
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The "thing" you're given at the beginning is unused and fully charged. That's why nobody can solve the mystery. The first time it's ever used is when you decide to use it.