How can someone be free if they can't even see their own cage? Even worse, what if they believed the very thing that was keeping them caged would someday set them free?
And what is it we want freedom from? Wants, needs, and desires? Fear, pain, and suffering? Daily toil, drudgery, and boredom? Money problems, relationship problems? All our problems? Wouldn't that be nice to not have to worry about all those things?
Let us go to the core, what is the root of all these issues? Simple, every single problem we have is a thought in our minds. A physical situation may exist, but it is the mind's reaction that makes it into a problem. Our own thinking turns it into a problem and through this we become slaves to the thoughts in our minds.
A prisoner who knows nothing other than prison would simply think that's the way life is. A prisoner who has tasted freedom will suffer far more when locked away, even though the reality of the situation would be the same for both prisoners. It's simply a difference in perception.
Because the mind can create the illusion that we aren't free, the illusion that we are dependent upon the body, mind and ego, the mind may seem very powerful. It's not powerful at all, but to a person who can only see through the filter of their mind, it's the most powerful thing in the world. The Being Within is where the power comes from, but that power is unconsciously given away by feeding into illusions.