Greeting Jim, yslim, and Louis,
I think I have views that are similar to Louis's, but may express myself differently. I find that some of the classics speak quite vividly to me, and some do not. Often there is a close correlation to what and how I have been taught. Those things I have not seen my teachers demonstrate are sometimes hard to grasp or hard to apply; whereas, those I have seen I can usually reproduce and verify in my own body. Where teachers stress different passages in the Classics or even different Classics, this may will affect the outcome. Also, since most of the Tai Chi Classics have a fairly transparent relationship to various aspects of traditional Chinese philosophy, practitioners are free to go "over the heads" of even known authors and reinterpret their insights in light of that philosophy.
There will be a nonmoving part of the body attached to the ground to provide the rooting. It would seem that only an external martial art which pushes off from the ground to generate sustained momentum to attack can qualify as "there is no part that does not move".
I don't find the concept at odds with the Wu Jianquan statement you quote (although I wish I could read his original remarks in Chinese), because there are different levels on which one can talk about action, movement, relative movement, and whether we're including mental intent in the category of movement.
I think I agree with Louis's statement. At the Association seminar in Buffalo this year, Yang Jun talked about the fact that we cannot fully talk about Yin-Yang terms without declaring first what the standard of comparison is. He talked mostly about empty and full, but I think this applies equally to movement and stillness. Empty and full of what? Movement and stillness with respect to what?
We know from Einstein that movement is a relative term. While this idea applies, of course, to special relativity, it also applies to describing the movements of the form. When we say that the hand "moves" in a particular way, do we mean that it moves relative to the forearm, a point on the floor, relative to the torso, or relative to the gaze? I find that there is often confusion about the differences, since we seem to use all of these references at one time or other.
In my view, when we talk about movement and stillness, we are actually talking about feelings that match certain bodily sensations and not something that a physicist would normally discuss. However, I do not like discussing things so subjective and often so vaguely understood as feelings, and so this is not how I translate the theory when thinking to myself. For me what it means is that "integrated movement/stillness" has an implication: the part partakes of the whole and vice versa. If you are trying to move, but one part does not, that means that in one sense the integrated whole does not move. On the other hand, if you are trying to be still, but one part is not still, that means that in one sense the whole and all its integral parts are not still.
One test exercise I like to do is to pick the Rollback Posture from our form and ask a student to move me laterally by simply "pushing" his or her arm against my side. I find that many people have difficulty with this. The reason is often that although they "move" their arm, they do not really "move" their elbow, since they feel it is not in contact with my body and does not participate in the movement. It remains "still." With the elbow still and empty, the hand becomes full and the energy leaks out to where the leverage is either non-existent or highly unfavorable. If one allows the elbow to "move," the proper Jin point on the forearm is engaged and it is not hard to move someone in this way.
Another interesting posture is Single Whip. By some measures, once we form our right hook hand, it remains still while the rest of the movement unfolds, thus apparently violating the stricture that all parts should be in movement. According to my understanding, however, our Single Whip does not violate this principle even so. Once I form the hook hand, my muscles remain actively engaged in lengthening and balancing the movement in my left arm and hand. To do otherwise would be like trying to hold a rubber band between your hands and trying to stretch it out while gripping with only one hand.
In our Opening movement, we do not move either the legs or the torso much and do not change height, and yet better players should still feel the energy come from the feet and be directed by the waist. This is almost entirely an "inside" movement, but if you look very closely at very good players, you may still see a slight change as they engage muscles and tendons.
As for "stillness," as we get better, we want to demonstrate a "settling" or sinking feeling ( "central equilbrium" = 中定) at the culmination of each posture. All parts must stop (but not stop). If some part is still moving by itself, you cannot get this feeling, and the change from Yang to Yin will not be crisp. And yet, if you look at some good players, their bodies are actually not completely still at this culmination, since there may be some "rebound." The required stillness and physical stillness are not quite the same.
Lastly, think of the movement of a slinky. For any part to move along the ground, all parts must eventually move. For any part to move, some other part must also be still. For any part to be still, the movement must go on in some other part. At the end of all movement, for any part to be still, all parts must be still. These statements on the surface are contradictory, but anyone who has played with a slinky can see the truth in all of them.
In these senses, at least for me, my rooting foot is very much "moving," even though it does not leave its position. In fact, to be still, my foot cannot be actively rooting. For me, the aphorism is very helpful and very descriptive.
I have heard this from the classical writing for some time I think this is another big error as well as "when one part moves..." , when it describes such a sequence and I see a different sequence for the generation of jin. One can think of reasoning for the following statement, but I also find my own experience of fa jin bears it out as well:
I see it rooted in the feet, generated by the waist, controlled by the legs and manifested through the fingers.
Could you elaborate on your reasoning for this particular sequence, for I think we may be giving a different meaning to these words? Your statement does not appear to match what I see in my teacher, what I feel in my own body, or what my students see in me. Also, some masters say that the waist governs the changes of empty and full. How could this be so if it is the primary engine of Fajin? Do you feel that Fajin can be "empty" in some way? How do you generate power in the kicks with your waist?