Awareness that we are thinking is a sensation

"Just as we sense where our mind "is," we must be informed as to what it is doing. Awareness that we are thinking is a sensation that happens to us; it is not a thought that we can consciously will. We feel that we are thinking in the same way that we feel bodily activity. Those thoughts that don't reach awareness aren't felt as being actively thought. Which leads us to the larger question of the role of mental sensory systems in differentiating conscious from unconscious thoughts."