Nine and six supplementation and drainage

A method of supplementing and draining in acupuncture that involves lifting, thrusting, and rotation actions performed in sequences of six or nine, and that is based on the yīn-yáng significance of odd and even numbers. The ancient Chinese believed that yáng numbers were odd and belonged to heaven, while yīn numbers were even and belonged to earth, and hence that supplementation could be achieved by sequences of nine, and drainage through sequences of six. For example, to supplement, a sharp thrust and gentle lift or an anticlockwise rotation is performed nine times. Once qì is obtained, another sequence of nine can be performed after a brief interval. One more sequence is then performed to make three sequences and a total of 27 movements of the needle. To drain, a gentle thrust and sharp lift or a clockwise rotation is performed six times. If the evil is still exuberant, the sequence is performed again after a short interval. A third sequence then makes 18 movements of the needle. Numerical determination of supplementation and drainage is now no longer considered to be of practical benefit, and the method is now rarely used.