In the episode of LOST from season 1 entitled "Outlaws", Sawyer meets Christian Shepherd in a bar in Australia. Christian tells Sawyer that he is too weak to do that which could fix everything - call his son and tell him that he loves him, and that he's grateful and proud because of what he did, rather than feeling betrayed. Christian talks about fate, and we learn that he had a saying, "That's why the Red Sox will never win the World Series".
As we've witnessed Christian Shepherd take on some rather startling qualities on the island since then, and become somehow interconnected with the island, we must ask the question: was Christian Shepherd somehow involved with the island, whether the "Others" or the Dharma Initiative? Was he involved in time travel? When he spoke of fate, did he really mean a future that he knew about and thus considered inevitable?
What was his role in getting not only Claire but also Jack and his own corpse on the plane that was "fated" to crash on the island?
What's most interesting is that Ben later shows Jack a video of the Red Sox winning the World Series. The most recent Dharma Initiative film suggests that some think the future can be changed. Perhaps the universe does indeed have a way of "course correcting", but if one makes a significant enough change at a significant enough juncture in history, then it produces an effect to large to be corrected for. Perhaps it is possible to change the past - and the future.
There's a nice summary of the episode on the Houston Chronicle's Tubular blog.