If the body is clumsy, then in advancing or retreating it cannot be free; therefore it most be agile. Once you raise your arm, you cannot appear clumsy. The moment the force of the opponent touches my skin and hair, my mind is already penetrating his bones. When holding up the arms, the chi (breath) is threaded together continuously. When the left side is heavy, it empties, and the right side is already countering. The chi is like a wheel, and the whole body must naturally coordinate. If there is any uncoordinated place, the body becomes disordered and weak. The defect is to be found in the waist and legs. First the mind is used to order the body. Follow the opponent and not your self (your own inclination). Later your body can follow your mind, and you can control your self and still follow the opponent. When you can follow your opponent, then your hands can distinguish and weigh accurately the amount of his force, and measure the distance of his approach with no mistake. Advancing and retreating, everywhere (the coordination) is perfect. After studying for a long time, your technique will become skillful.
Red.: from Five Character Secret (Calm, Agility, Breath – to gather the chi, The internal force – the complete chin, Spirit – Shen concentrated).
Reference: T’Ai Chi Ch’Uan Ta Wen, Questions and Answers on T’Ai Chi Boxing Chen Wei-Ming ( Benjamin Pang Jeng Lo & Robert W. Smith ) North Atlantic Books 1985