Here's my big Season 6 Theory:
Jacob and MIB represent the full potential / guiding force of the human race. They were created as the guardians or watchmen for humanity by some form of higher power, and The Island was created in order to give them privacy and closure from the rest of the world. Jacob and MIB were not created as inherently good or evil entities; they simply represented the balance that exists between life and death.
Jacob(white)was given power over guiding human beings and making sure they led civilized / moral lives, and MIB was given the power to use death as a check for anyone who abused the privelage of life. Furthermore, MIB (dark) was in charge of making sure those who led good lives transitioned smoothly into the next …Read more >