This is my 1st crack at this so bear with me.
My theory says that when you leave the island a portion or imprint of your soul / spirit remains behind, sort of a placeholder if you will. Those who have read The Dark Tower series will recognize this as somewhat like going "todash". This imprint might become a part of Smokey, may be included amongst the Whisperers or just may be hanging out in Jacob's cabin. In any event, if you knew that part of your soul was on an island and that you wouldn't be "whole" without it, wouldn't you move heaven and earth to try and get back (Widmore anyone?). This, I believe, is why Jack wants so desperately to get back. "Bentham" explained this to him and he believed it.
My theory further states that if your DEAD body is returned to the island and is rejoined with the soul imprint then you "come back to life" as it were (Harry Potter fans will liken this to Horcruxes). I believe that Christian Shephard was on the island at some point (part of Dharma??) and cam back into being when his dead body was returned to the island. The same will happen with John Locke.
Now, what I'm not sure of is what happens if you return to the island ALIVE while your imprint is still running around. Perhaps that what was Ben meant when he claimed that he couldn't go back.
Therefore, my guess is that the O-6 will have to die prior to returning to the island, perhaps in a plane crash...
Theory by younghutch
My theory says that when you leave the island a portion or imprint of your soul / spirit remains behind, sort of a placeholder if you will. Those who have read The Dark Tower series will recognize this as somewhat like going "todash". This imprint might become a part of Smokey, may be included amongst the Whisperers or just may be hanging out in Jacob's cabin. In any event, if you knew that part of your soul was on an island and that you wouldn't be "whole" without it, wouldn't you move heaven and earth to try and get back (Widmore anyone?). This, I believe, is why Jack wants so desperately to get back. "Bentham" explained this to him and he believed it.
My theory further states that if your DEAD body is returned to the island and is rejoined with the soul imprint then you "come back to life" as it were (Harry Potter fans will liken this to Horcruxes). I believe that Christian Shephard was on the island at some point (part of Dharma??) and cam back into being when his dead body was returned to the island. The same will happen with John Locke.
Now, what I'm not sure of is what happens if you return to the island ALIVE while your imprint is still running around. Perhaps that what was Ben meant when he claimed that he couldn't go back.
Therefore, my guess is that the O-6 will have to die prior to returning to the island, perhaps in a plane crash...
Theory by younghutch
