Here is thought that rolled into an a amazing theory. I was thinking about the DHARMA logo and the Bagua Map relation.
If you notice there are eight sections. This has to mean something.
This is when I thought about Jack's tattoo.
Now look at the white section the Bagua Map. Solid bar, solid bar, two bars. Look at Jacks tattoo. So, maybe there is a pattern; Jack represents the white section. Following this logic I would place Sawyer as Red, Jin as Pink, Hurley as Grey, Locke as Black (Life path),Sayid as Blue, Kate as Green, Sun as Purple.
The colors are up for discussion.
In Mysteries of the Universe they talk about the symbol meaning defense from all sides or something of that sort. So here's where it gets trippy. So when Jacob is pushed into the fire he goes in eight different directions in space and time. This is his defense. He travels to a time in these peoples lives (our colors above) so that they will arrive on the island in order to fight the final battle.
Now look back at Jack's tattoo. Maybe the five means that that it will be five on three or something. The tattoo is making a circle shape similar to the Bagua Map. And if I got my colors correct that means Jin, Jack and Hurley vs. Locke (dunno bout the whole dead think) Sayid, Kate and Sun. And that is the thought that rolled into a theory.