The body is a collective community of trillions of individually living cells that are all cooperating together to make a larger whole. The brain's cellular neural network, and its thoughts and thinking, are just another part of that overall cellular functioning.
The heart pumps blood all by itself without you doing it, the lungs breath air all by themselves without you doing it, and the brain associates self-invented concepts with other self-invented concepts all by itself. The vast majority of the time, the mind is thinking (randomly babbling) completely on its own. It has nothing to do with "you" doing it. If you look inside even for a brief minute you'll see that words, verbalization, thoughts, thinking, and emotionalism are completely automatic. The brain works all by itself, which means that you are not the doer of deeds, nor the thinker of thoughts.
So if the mind and body are working all by themselves as a result of cells doing work, why do we identify the mind's thoughts and the body's actions as being "me"? Are we the mind and body, or are we the Energy/Life/Consciousness/Awareness within the body that is simply aware of Itself as existing? Are we the mind and body, or are we the Awareness that is watching the body/mind's automatic functioning? Are we the doer and thinker, or are we the Silent Formless Observer?
Out of being identified with the body/mind, we are being controlled by it. We are enslaved by it because we falsely identify it as being "me".