How Jacob and Eloise Knew About the Future by Jhisc9999

I think Jacob could see the future and that this was made possible by the Losties’ time travel back to 1977. The light is in each of us, so the light traveled back too and Jacob could connect with it. He could see events that were to occur, especially death. This is why he ordered the runway to be built. I think he shared this gift with Eloise and that she could see flashes (like Desmond) of the future. Hence, she knew about the man in the red shoes. Desmond's flashes were also about someone who was going to die - Charlie. Jacob's and Eloise's clairvoyance was limited to the point when the Losties vanished off the Ajira flight. From that moment on, neither knew what was going to happen.

This knowledge of what was mostly going to happen was his advantage over MIB. He had to use this in some way to defeat MIB, but he had to let what ever happened, happen (at least the important stuff). Otherwise, he would lose his advantage. He knew what MIB was plotting, but he had to let it play out. I don’t think Jacob was committing suicide when he died because he could no longer see the future when Ben killed him which is why he was hoping, at that moment, that Ben would not do it. He was willing to take the risk, though, because someone needed to do what he could not, kill MIB.

Enter the Losties and Desmond, Jacob’s wildcard with the ability to be exempt from the rules. As such, he needed to be watched and steered into his path. This is why Jacob gave Eloise her gift of clairvoyance so that she could monitor Desmond. She noticed something different about Desmond and inserted herself into the Jewelry store to set him straight. In the end, Jacob would use Desmond to defeat MIB by seemingly giving MIB what he wanted, a way to destroy the light. MIB wasn’t counting on what would happen next, that he would lose his powers and be destroyed by the Losties. This was Jacob’s best chance of defeating MIB and protecting the light. He needed the Losties and they all needed each other.

This is one of the best stories ever told and it keeps giving.