10 Essential Points:

• 1. Head upright to let the spirit rise. Don't use external strength, or the neck will be stiff and the qi and blood cannot flow through. It is necessary to have a natural and lively feeling. If the spirit cannot reach the head top, it cannot raise.
• 2. Sink the chest and lengthen the back. The chest is depressed internally so that the qi can sink to the dan-tian. Don't expand the chest as the qi can get stuck and the body becomes top-heavy. The heel will be too light and can be uprooted. Pluck up the back and the qi sticks to the back; depress the chest and you can lengthen the back. Then you can discharge force through the spine.
• 3. Relax the waist. The waist is the commander of the whole body. If you can relax the waist, then the two legs will have power and the lower part will be firm and stable. Substantial and insubstantial change, and this is based on the turning of the waist. It is said "the source of the postures lies in the waist. If power is lacking, seek the defect in the legs and waist."
• 4. Differentiate between insubstantial and substantial. This is the first principle in T'ai Chi Ch'uan. If the weight of the whole body is resting on the right leg, then the right leg is substantial and the left leg is insubstantial, and vice versa. When you can separate substantial and insubstantial, you can turn lightly without using strength. If you cannot separate, the step is heavy and slow. The stance is not firm and can be easily thrown off balance.
• 5. Sink the shoulder blades and drop the elbows. The shoulders will be completely relaxed and open. If you cannot relax and sink, the two shoulders will be raised up and tense and the qi will rise so that the whole body cannot get power. "Drop the elbows" means the elbows go down and relax. If the elbows raise, the shoulders are not able to sink and you cannot discharge people far. The discharge will then be close to the broken force of the external schools.
• 6. Use intention instead of force. The Classics say, "all this means is to use mind-intent and not external strength." In practicing Taijiquan the whole body relaxes. Don't let one ounce of force remain in the blood vessels, bones, and ligaments to tie yourself up. Then you can be agile and able to change. You will be able to turn freely and easily. Doubting this, how can you increase your power?
• 7. Coordinate the upper and lower parts of the body. The Classics say "the motion should be rooted in the feet, released through the legs, controlled by the waist and manifest through the fingers." Everything acts simultaneously. When the hand, waist and foot move together, the eyes follow. If one part doesn't follow, the whole body is disordered.
• 8. Harmonize the internal and external. In the practice of Taijiquan the main thing is the shen/spirit. Therefore it is said "the spirit is the commander and the body is subordinate." If you can raise the spirit, then the movements will naturally be agile. The postures are not beyond insubstantial and substantial, opening and closing. That which is called open means not only the hands and feet are open, but the mind is also open. That which is called closed means not only the hands and feet are closed, but the mind is also closed. When you can make the inside and outside become one, then it becomes complete.
• 9. Move with continuity. As to the external schools, their jin is the Latter Heaven brute jin. Therefore it is finite. There are connections and breaks. During the breaks the old force is exhausted and the new force has not yet been born. At these moments it is very easy for others to take advantage. Taijiquan uses intent (yi) and not external strenghth (li). From beginning to end it is continuous and not broken. It is circular and again resumes. It revolves and has no limits. The original Classics say it is "like a great river rolling on unceasingly." and that the circulation of the qi is "drawing silk from a cocoon".
• 10. Move with serenity, seek stillness in motion and motion in stillness. The external schools assume jumping about is good and they use all their energy. That is why after practice everyone pants. Taijiquan uses stillness to control movement. Although one moves, there is also stillness. Therefore in practicing the form, slower is better. If it is slow, the inhalation and exhalation are long and deep and the qi sinks to the dantian. Naturally there is no injurious practice such as engorgement of the blood vessels. The learner should be careful to comprehend it. Then you will get the real meaning.

Yang Cheng-fu (1883 - 1936)  father of the Yang Long Form