We can find ourselves stuck in box with no apparent way out which is caused by our thinking. If we think something is not possible for us then we are in the box and all we do is keep bouncing off the walls of our limitations which are self-imposed.
By changing our thinking from not possible to it is possible but we just don't know yet how it will happen so we will change how we question and what we question. This creates possibilities that will lead to new decisions and actions and before we know it we are no longer in the box.
Another way of putting this is that what we believe is our reality and we always work within our reality. Change our mind and we change our reality.