- The hand and foot must have a connection through the waist, or dantiian area. In this case the waist becomes the modifier.
- The hand and foot must stay on a curved or straight line, causing this connection.
- Opening means to move outwards, causing the distance between the hand and foot to lengthen.
- The hand and foot can never move towards each other (please note that the meaning of this requires further clarification later on).
You can see this principle in action in the video clip through the link below.