Before Heaven & Earth existed, within the inexhaustible Emptiness was the Undivided One Qi, known as Wuji. Wuji gave rise to Taiji. Taiji is Heaven & Earth’s foundation & root, the origin of the Ten Thousand Things . In Taijiquan, as soon as there is movement, the whole body without exception must be light & agile, & it especially must be threaded through. The Qi should vibrate like a drum, & the Shen should be collected within. Do not allow there to be cracks or gaps anywhere, do not allow there to be bulges or depressions anywhere, do not allow interruptions anywhere. It’s root is in the foot, emitted by the leg, dictated by the waist, & expressed by the fingers. From the foot to the leg to the waist, it must be complete & a single Qi. Whether moving forward or retreating backward, you‘ll be able to seize the opportunity & become dominant. If there isn’t an opportunity to seize the advantage then the body will fall into disorder, the defect is certainly in the waist & legs, seek it there. Upper & Lower, Front & Rear, Left & Right, it’s all the same. This is, in all cases, about Intent, not an external concern but an internal one. If there is Above then there is Below, if there is Front then there is Rear, if there is Left then there is Right. If you need to rise upward then that implies a downward Intention. If your opponent desires to raise something, then you add Filing to his Intent. Do this & he’ll break his own root, you will undoubtedly repel him quickly. Empty & Solid must be distinguished clearly. Each place has a part that is Empty or Solid. Everywhere is always like this, both Empty & Solid. Every part of the whole body must be strung together, do not allow the slightest interruption.
(Yuan Zhu said: “This relates to the Theory bequeathed by Mount Wudang’s Teacher Zhang Sanfeng. He wished for all the heroes Under Heaven to attain longevity, & not merely cultivate Martial Skills.”)