Both Kwon's are 42= MIB doesn't know about the Lighthouse by rosebud

When MIB took Sawyer to the cave with the numbers, he said he didn't know which Kwon- Sun or Jin- was 42. When Sawyer asked what the numbers meant, MIB said that Jacob had a thing for numbers. As we now know, the numbers represent the degree markings in the Lighhouse that match up with the candidates, it seems to me that it represents both Sun and Jin (especially as Jacob touched both of them.)

Now, it is entirely possible that MIB lied about the numbers, but why bring up the Kwon's at all? I think he truly didn't know about the Lighthouse. So, I think that:

A. The Lighthouse is not something that is meant to be seen until you are ready to see it (or Jacob is ready to let you see it), as evidenced by Jack's comment about not seeing the Lighthouse before.

B. MIB would surely have seen the lighthouse before, as he apparently has been on the island for a very long time. So, this is something that is hidden from him. This brings up a question, though. If Jacob could keep the names of the candidates hidden from MIB, why write them on the walls of the cave? Wouldn't he want to protect his candidates from being interfered with?

C. I think that MIB is limited to the island and cannot appear off-island or affect events in the real world. So, I think that Ben killed Locke on his own. But, a dead candidate is what MIB needed to get close to Jacob to gain access and kill him. So, he took advantage of the opportunity of dead Locke. However, as discussed before, Jacob completely knew Locke was dead and that MIB was doing this, so he used it to his advantage (kind of like Obi Wan Kenobi).

So, however this game is being played out, it seems that Jacob has an advantage of seeing off-island and interacting off-island. On the island, MIB has an advantage in that he can take the form of dead people on the island. He can use this to manipulate the candidates to destroy themselves, and Jacob has to keep finding new candidates.