Has anyone ever put forth the idea that Jack died that first day in the jungle? What if-- Smokey/Jacob or whoever's doing the controlling reanimated Jack, and in doing gained some control over him. The person has free will BUT they are heavily influenced by whomever is "in" them. Could this be possible? Remember when Juliet was first introduced she made a comment at the bookclub about "thinking freewill still exisited on the island" which was cut short by 815 breaking up. This could explain some of the wishy washy behavior of some characters. Remember in Expose "you are the cobra, all the time it was you". Maybe the reason they weren't suppose to leave the island is because a presence was in them that was supposed to stay on the island. Maybe Jack is the Cobra. I think Jack is the KEY to the whole shebang. When I watch older episodes with my new season 5 knowledge I just bust out with what ifs.