They say taijiquan is a “martial art,” which is essentially the art of being aware of one’s self in a time and moving from a place of stillness, maintaining it in the midst of movement. I understand this place of stillness as “wuqi,” which has many definitions among various pratitioners. The “state of undifferentiated being,” “standing like a mountain,” “unselfconscious oneness,” “empty, yet alive, changeable, agile, quiet.”
Taiji is born out of Wuqi, the classic states, and it returns to Wuqi. Movement to stillness to movement to stillness. Yin to Yang to Yin and so on. This suggests leaving and returning. But it is possible that Taiji never leaves Wuqi and Wuqi is always present in and of every movement. This is stillness in movement that some refer to. Your awareness never leaves Wuqi even while your body flows in and out of yin and yang.