Yogis and Sufis, therefore, and all students of the inner cult, believe that breath is the means of receiving all intuitive knowledge from every direction of life. Absorbed in a thousand things of daily life man gives very little thought to breath. Therefore he keeps his heart closed to all the revelation that can be received by the help of breath. Man as a rule is never conscious of his breath, of its rhythm, of its development, except at the time when he is so tired that he is breathless or when he is so excited that he feels choked up, or when something keeps the breath from flowing.