*The title of the French song Shannon translated clear back in Season 1 was “Beyond the Sea.” It includes the lyrics “It’s far beyond a star, it’s near beyond the moon. I know beyond a doubt, my heart will lead me there soon.” This coupled with the “Catch a Falling Star” theme is making me strongly lean toward an extraterrestrial explanation.
*When the Boy in Black suggests the possibility of other places across the sea, his “mother” tells him, “The island is all there is.” I’m thinking we are dealing with metaphors here. The earth is an island and space is the ocean. We think that earth is all there is.
Later, he asks her what a “ship” is. She says it’s a way to get from one place to another.” Like a spaceship?
*When the “mother” shows the boys the Light, she says that it contains “life, death and rebirth.”
*The Man in Black and the “mother” are Adam and Eve. When Jack found the skeletons, he said the clothing was about 70 years old. Either this is a minor inconsistency in the story or Jack is no forensic expert.
*The Boy in Black tells Jacob, "One day you can make up your own game and everyone else will have to follow your rules." This ties in with what young Jacob says to BadLocke: "You can't kill him. Those are the rules." Games play a great significance in this series.
OFFICIAL THEORY as of May 17th.
I think the island contains or is an interstellar ship. Unfortunately, I think the plot is also headed toward the origin of life being extraterrestrial. The ship came to earth long ago and life on Earth came from it. It continues to sustain life here. This might explain the electromagnetic anomalies. This would also explain the island’s ability to move through time and space.