virus1 said:well the difference is that dave never did exist in hurleys life before the island, actually. i think the reason he was able to talk to dave and jack couldnt was because he was able to in his past ( and it was still a hallucination). i think that the island is only as real as the people on it believe it to be, otherwise, who knows? the point is that nobody knows, so enjoy the show on whatever level it actually is on.
One thing id like to add though is that dave and desmond's last phrase was the same. They both said "See you in another life" before disappearing.