Center line concept
Imagine a silhouette of a person with a line drawn from the top of the head threw the nose, abdomen, groin and into the floor, cutting the person in half. This is the center line and is used by many MA styles from the internal styles, tai chi, bagua, x\ing yi, to the external styles wing chun, and kempo mention in an earlier thread, in addition savate a French kicking art, western boxing, bando boxing from Burma and many, many other styles advocate the use of a center line.
All these styles can get confusing in the eyes of the laymen so forget all the styles and names and focus on the concept “a line that cuts something in half.” the center line.
You don’t need a 6th degree Master, or a 300 year old Taoist scroll to teach you to hit‘em in the Labanza!!! Aim for the middle (center line) The center line concept is not a wing chun or kempo concept, it is common sense and realized by all sorts of MA styles in addition to archery, firearms, fencing etc. go for center mass and there is a good chance you will hit something.
Of course common sense would dictate that you might want to put up some sort of barrier so you don’t allow someone else aiming at “YOUR” center line, so the arms, elbows, knees etc are positioned to block out your center line.
Someone mentioned in another thread about pivoting on center line, once again this is not a concept exclusive to any one style or even MA IMHO this is science. If we expand on the notion that not only the body is a silhouette, but also has width, height, and depth as mentioned earlier we now can imagine that the center line may resemble a pole that can be from the top of the head right threw the body into the floor allowing the body to pivot or rotate. This is no more then the idea of a basic machine, a wheel and axel. When the wheel rotates it causes centrifugal force and a 360 degree defensive barrier can be used.
The center line concept is not the end all but merely another tool to be recognized by one who is trying to learn the science of movement and develop their own style.