My theory is that the Losties can only be on the island or back on earth; they cannot occupy both at the same time. Clue: Ben said if Jack answered that phone contraption, everyone would be dead.
I believe they will be rescued, only to return to their earthly realities. CLUE: Ben asked what was Jack trying to return to, hinting that he knew Jack's life was, well, Jacked Up (I couldn't resist the pun).
Once they are rescued, Jack realizes that Ben was right. I believe Ben is the dead man in the coffin CLUE: Jack said the dead person was neither a friend or family member, and Jack visits him because he realizes Ben had their best interests at heart.
Jack tries to get back to the island so he can have Kate. On earth, Kate meets up with and marries Sawyer. CLUE: Jack told Kate he loved her and their relationship was warming up. Jack knew that in time, Kate would be his. However, on earth Kate had to get back to her husband.
I believe Ben and Locke are brothers but Locke is still on the island. CLUE: Locke walks away when Jack answers the phone, but Ben is held captive. Locke and Ben also have mothers named Emily. Because they are brothers, they both have that sixth sense type of thing that allows them to hear Jacob. Ben is jealous of Locke because he knows they are related and Locke is the only other person who hears Jacob.
Jacob is a manifestation of everyone's fears, hopes, and dreams. He knows all about them (therefore Ben knows what Jacob knows). I also believe that Jacob is a spiritual being and can appear in many forms (he appeared as Walt when Locke was in the pit with the Dharma remains, and perhaps as Ben's mother, Jack's mother, and other characters who only appear as ghostly images).
Share your thoughts on geekytutor's theories in the Island or Earth blog post.
