The nine requirements are: 1. sinking, 2. hollowing, 3. lifting, 4. pressing, 5. wrapping, 6. loosening, 7. hanging, 8. shrinking, 9. clearly distinguishing between lifting, drilling, dropping, and overturning.
“Sinking” means your waist has an energy of sinking down, the principle of your tailbone lifting and activating your Du meridian.
“Hollowing” means opening your chest [inwardly] to smooth your energy, the principle of passive energy descending along your Ren meridian.
“Lifting” means to lift your rectum inward.
“Pressing” means your tongue touches your upper palate, your head presses up, and your hands press up.
“Wrapping” means your elbows have an energy of wrapping inward. If your hands are propping something up, palms facing upward, there has to be such an energy of wrapping inward.
“Loosening” means loosening your shoulders as when drawing a bow, keeping your elbows from poking outward.
“Hanging” means that when your hands twist outward, your elbows have a strong energy of hanging down.
“Shrinking” means your shoulders and hips have a strong energy of shrinking in.
As for “lifting, drilling, dropping, and overturning”: lifting is drilling and dropping is overturning. Lifting is horizontal and dropping is vertical. Lifting and drilling are threading. Dropping and overturning are striking. But when lifting is also striking, dropping is still striking. Strike with lifting and dropping, like the wheels of machinery spinning continuously.
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Although the arts of Xingyi and Bagua are divided into associations with the square circle and round circle, their theory is simply to restrain your power while moving, causing your energy to consolidate and return to your elixir field. Great sages by such means possessed discipline and sincerity, both of which are closely linked to the way of boxing arts. Great heroes trained both wisdom and courage. You likewise must begin by understanding the mathematical concept [of the trigrams]. Great artists broadened their understanding by deeply studying things. You likewise must begin by understanding the function of intention, energy, and power.
Even though the postures of both arts are different, their principles are the same. While practicing these arts, understand these principles. Use your elixir field as the basis, take intention, energy, and power to be the function, and let the nine requirements be the standard. If you practice according to these principles, then even if you do not achieve mastery, you will nevertheless not be far from it.
And, of course, there are eight mother palms, eight postures, used in walking the circle - here are four.
Millstone Pushing