Answer:
At the center of each persons's won vantage point of the world is their consciousness.
Explanation:
One's consciousness is a state of being aware and the way the individual perceives his/her surroundings. It's a state of mind and the individual's personal point of view in the world.
When Obi-Wan is discussing this with Luke, he is referring to his consciousness because everything he knows depends on this. It is his state of mind and his state of awareness and perception of the world surrounding him.