We are not in as much control of ourselves as we believe. There are powerful heuristics and evolutionary motivators that we simply aren't aware of at the conscious level.

How often do we retroactively create a reason for our actions after they've already been taken? A reason that is internally consistent with our personal narratives about who we are as people.

I've always been intrigued by this study out of UNSW. They could predict a subjects choice up to 11 seconds before the the subject was consciously aware of it by examining brain function.