You have no idea what I went through to be here by 9innail

I've been doin some thinking since last episode, and there are some cool things that may or may not show some of the rules. So, Jacob through MIB into the light, and in so doing seperated his "soul" or "life force" from his physical body. So perhaps when someone dies on island, their "life force" is returned to the "source", allowing MIB to assume any form of on island dead. Ah, but what about Christian who died off island? Well I think either a) MIB copied his physical form and then moved his body out of the coffin and hid it, or b) off-island dead are only vessels and not "candidates" for having their forms mimicked. Since Locke died off-island and was still copied, I think (a) is right. The whispers are of course ghosts that can't move on, and therefore are not candidates for physical copying, but only for appearing subliminally in one person's vision at a time. (Christian on the freighter).

Wouldn't it be wild if the boy Jacob that Sawyer, and Desmond saw at the same time as Flocke was an aspect of the rules mocking MIB by smiling and saying, "HAHAHA, you didn't think of this one as a candidate did you?", which is why Flocke at first chased the boy, confused, then when he was with Desmond, just said "ignore him"? Now that i think of it, that line "You have no idea what I went through to be here", is very chilling to me. Probably the last time Jacob saw any trace of MIB in physical form was when he was on the log talking to what he knew could not be the physical form of his brother, but only an expression of his brother's new powers, which he completely was aware of, but didn't seem too impressed by. this could seemingly open up a new door, like the reason Smokey scanned people and judged them was because of the memories of the dead whose "life force" returned to the "source", like with Eko. Anyway, so some rules are most likely...

Jacob - never tells people what to do, they make up their own minds. which is why they can choose whether or not to trust Richard. Also if someone asks to see jacob, the answer is only "be patient", which in so doing you aren't choosing for yourself, but accepting a command to be patient. If you really choose for yourself to go see him, no one can stop you, it's your choice. no direct contact with anybody that does not choose to have it completely.

MIB - can assume the form of anyone that is dead, and will best convince people to trust him. cannot kill Jacob's "pawns" directly, just like chess, he strikes diagonally :) by getting them to kill each other with nothing more than a convincing argument or stressful circumstance (i really believe the bomb on the sub wouldn't have gone off if they would have let the timer reach zero, because that would violate the rules. lucky for him, he knew sawyer wouldn't trust Jack anymore.)
There is so much more to add to this that would only validate the rules more, so I hope you guys can think of some in the comments, thanx.