Bob wrote:https://www.youtube.com/watch?v=MitDyQU1rh0
Tai Chi (Chen Style) Part 01 陈氏太极拳-缠丝功【上】陈小旺
武禹襄 Wu Yuxiang or Wu Yu-hsiang (1812–1880) was a Chinese T'ai chi ch'uan (Taijiquan) teacher and government official active during the late Qing dynasty.[1] Wu was a scholar from a wealthy and influential family who became a senior student (along with his two older brothers Wu Chengqing 武澄清 and Wu Ruqing 武汝清) of 杨露禅 Yang Lu-Chan.[1] Wu also studied for a brief time with a teacher from the Chen family, Chen Qingping, to whom he was introduced by Yang.
[Discussing how to 'Fajin' (Issuing/ Emit/ Send power out from the Dantian)] by 武禹襄 Wu Yuxiang (Practitioner of Yang and Chen Family Taijiquan), (but credited or said to be the teachings of Wong Zong-Yue):
蓄劲如开弓,发劲如放箭。
Xu jin ru kai gong, Fajin ru fang jian.
Building up force (jin) as if pulling back the string of a bow/ Drawing Open (開 Kai) the Bow, Emitting the force (jin) as if releasing the arrow.
曲中求直,蓄而后发。
Qu zhong qiu zhi, xu erhou fa.
As the straight is bent, or curved, Gathering (force) then Emitting (fa).
力由脊发,步随身换。
Li you ji fa, bu sui shen huan.
Power comes from the spinal column emitting (force), the changes of the body go along with the stepping.
收即是放,连而不断。
Shou ji shi fang, Lian er bu duan.
[But, unlike the Bow and Arrow] Gathering quickly is releasing, they're linked together and can repeat unceasingly [Where the Arrow can only fire once].
往复须有折叠,进退须有转换。
Wangfu xu you Zhedie; Jintui xu you Zhuanhuan.
Going out and coming back must use 'Zhedie'. Entering and exiting must use 'Zhuanhuan'.
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In 'Zhedie', the key is where the 'Horizontal Middle Axis/Axle' (横向中轴 Hengxiang Zhong Zhou) is going through your body. This should be about the same height as your navel, because if you follow a straight line from 'Qihai point' back to 'Mingmen point' it's at an angle so the center of this/ true Dantian, is where the Horizontal Axis crosses from side to side.
The other key is that it's the 'Tailbone Gate' (called 尾骨闾 Weigu Lu in CIMA vernacular) that moves the Dantian around it's Horizontal Axis.
When the tailbone tucks under, it's like a gear that turns the Chest (Upper torso) in the opposite direction. As seen in this animation:
The Dantian is the 'Core' (核心 Hexin) of the movement. It moves, then every other part moves because of it's 'Influence'. (一动全动 Yi Dong Quan Dong "One part Moves, Every part Moves" aka 万法归 Wan Fa Gui Yi "The Ten Thousand Methods all come from One")
So it's the Zhuanhuan (turning of the Dantian on it's Vertical Axis) and the 'Zhedie' movement of the Dantian (Rotating it on it's horizontal axis), that then 'Influences' (影响 Yingxiang) the Shoulders, elbows, wrists, hands and also the Hips (kua), Knees, ankles, feet.
It is a difficult thing to distinguish the Hips (kua) from the 'Tailbone Gate' ( 尾骨闾 Weigu Lu), and it's just a matter of inches (Cun), but "Off by just an inch (cun) and later you'll be off by a mile (Li)." and on the other side of the coin the literally 1 Cun of movement that the 尾骨闾 Weigu Lu (Tailbone Gate) does, will translate to power that feels like miles. Like a Blackcat firecracker, a lot of power contained in a small movement. (Same thing with 'Zhuanhuan' - just 1 degree of rotation at the core (核心 Hexin) of the Dantian, becomes so much more when it's out at the hands.)
A lot of people in the IMA world have developed 'Zhuanhuan' but not too many people have figured out how to find their 'Zhedie' power.
Some people have learned how to use their 'Kua' (hips) to compensate for the lack of 'Zhedie', but it's not the same, it's self-limiting, as there is never the possibility for finding all the other more advanced Internal techniques that come from the 'Surging' (Bo) power of tucking and the 'Returning' (Fan) Power of untucking the 尾骨闾 Weigu Lu (Tailbone Gate).
Again:
往复须有折叠,进退须有转换。
Wangfu* xu you Zhedie; Jintui** xu you Zhuanhuan.
Going out and coming back must use 'Zhedie'. Entering and exiting must use 'Zhuanhuan'. ~ Written by Wu Yuxiang
*往复 Wangfu (to go and come back; to make a return trip / backwards and forwards (e.g. of piston or pump action) / to reciprocate (of machine part))
**进退 Jintui (to advance or retreat; knowing when to come and when to leave)
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