One who does not breathe fully, in other words freely and deeply, can neither be well physically nor make use of his mental faculties. Very often one finds most learned and intelligent people unable to work as they wish and incapable of finishing a work which they have taken up. Sometimes a person thinks it a bodily weakness or mental weakness or lack of enthusiasm or loss of memory, not knowing that it is very often a matter of regularizing the breath. Most often people think that it is the external senses being tired or exhausted that prevents their thinking, but in reality it is the absence of right breathing, for right breathing can make the mental faculties clearer and the outer organs of the senses more capable of perceiving.