The Pi 
-Shen 
relationship is a kind of mutual nourishment and interdependence. Pi is the root of an acquired base (post-birth); Shen is the root of a congenital base (pre-birth). If Pi –Qi is deficient, Qi cannot replenish Shen-Essence, causing tiredness, abdominal distension, weakness of the waist, tinnitus, and dizziness.
