Tai-Chi essential 7 of 10: 上下相随 (Top follows bottom)
上下相随 上下相随者，即太极拳论中所云:其根在脚，发于腿，主宰于腰， 形于手指，由脚而腿而腰，总须完整一气也。手动、腰动、足动，眼神亦 随之动，如是方可谓之上币相随。有一不动，即散乱也。
My rendition of essential 7: “During practice, one’s bodily movement must follow this sequence: feet, leg, waist, arms, hands and finally fingers, in one single transmission of chi”. Needless to say, the eyes must be alerted during the whole process. If just one of these links doesn’t move according to the sequence, the whole body will wobble during from practice.
Paul’s additional comment: This essential must be executed together with essential six. Combining these two essentials, the body will be conditioned and the movement will both be graceful and powerful. An important practice concept of this essential is transfer chi upwards through spiral movements (a separate post for the subject of spiral movement shall be done on a later day, stay tuned).