"Don't Think You Are. Know You Are."
In the movie, "The Matrix", Neo's (Keanu Reeves' character) education - his understanding, acceptance of, as well as his ability to fulfill his true potential - is centered around belief.
Belief that the world as he has known it has been defined by someone else's rules.
Belief that these rules are there for a specific purpose, and that this purpose is not only serving someone else's goals, they are limiting his true potential.
Belief that some of these rules "can be bent, others can be broken", thereby allowing him to see, alter and shape reality as he sees fit.
This is exemplified in one incredible training scene between Neo and Morpheus, where they engage in a fight to illustrate Neo's newfound expertise in Kung Fu. Morpheus essentially schools Neo until he begins to learn.
That the path to achieving his potential lies not in his technique, no matter how good. Nor does it lies in his physical strength or his speed in the world he inhabits.
That his path is dependent on his ability to know who he is, and not simply conceptualize or idealize what he could be.
And until Neo comes to this complete acceptance, he will flounder, living by someone else's rules, the odd win here or there, but ultimately several steps short of becoming who he could be (frankly becoming much more than he thinks he could be).
This central lesson - don't think you are, know you are - is the central lesson of our lives.
It is the single defining belief that governs our ability to succeed, far more than talent, far more being 'lucky'. It pushes us beyond ourselves, allowing us to defy 'conventional wisdom', to redefine it.
And the lack of it holds us back. Literally - physically, mentally, spiritually - holds us back. It's the reason we imagine a world for ourselves but don't take that next step to bring it to life. It's the reason we stay silent and don't speak up, push outwards, break with what is considered normal.
Normal. Someone else's normal. The normal that fulfills someone else's goals. That uses us as a simple cog in their system. To further their agenda.
Breaking that hold requires us to have belief. After all, those rules we don't like were designed by someone who didn't like the original set of rules they lived with in the first place.
Don't think you are. Know you are.
Believe it. Then go do it.
Make the mistakes. Fall down. Get hurt.
Then get up and try again. As the saying goes, "Fall down nine times, get up ten".
It all starts, endures and ends with your belief.