A mistake that many students of Taiji make is to assume permanently the dreaded Taiji slump: an over hollow chest, over rounded shoulders, a distended belly, and a head that cranes forwards into one's personal space and out of vertical alignment with the heart and dantien. It stems from a masturbatory obsession with one's own feelings and energy, and a neglect of what the Dao De Jing calls virtue. It is the Taiji equivalent, though opposite, of the puffed up chest and pulled back shoulders of proud Yoga practitioners: an ostentatious display at best. The Taiji Classics say to keep to a yielding mind, but yielding is not a state but a fleeting change of state designed to softly connect to an incoming energy that would not have imposed itself had you been yielding before it arrived. And if the world stops imposing itself – stops making demands – then boredom and depression ensue. Verticality of posture is one's connexion with Heaven and Earth without which everything in life is out of balance and so liable to corruption.