Although the concept of a Centerline is not unique to Wing Chun Gung Fu, it is visualized and applied in no other martial arts system in the same way. Aside from the Centerline, the Wing Chun man employs pyramidal, circular, angular, and linear structures to defeat opponents through scientific technique rather than brute strength or speed. Proper use of the Centerline, also known as Seen Wai Miu Yoang in Cantonese, heavily relies on correct Self-Structure and, in turn, adequate application of that structure to that of the opponent. The “Concept of Reference” refers to this combination of form and combat application. Wai Jee, or reference, is similar to target shooting in that it requires setting the sights of a rifle to pinpoint accuracy and then aiming that rifle with equal precision. The Self-Structure (the gun sight) and the Applied Structure (the marksman’s aim) should be as accurate as possible. If either element is incorrect, the execution will be subpar and may fail. However, suppose the Wing Chun practitioner’s technique is correctly structured in terms of reference. In that case, he can combine power, focus, and positioning to maximize the effectiveness of the method at hand.
Yin and Yang Motion—The Yin and Yang principles determine the reference and, thus, the application of a technique. To fully understand how this concept works, the reader must first understand the Centerline Theory and The Cutting Angle, which have already been discussed. He must also be familiar with the concepts of Yin and Yang, as well as “The Arc of Power,” which will be discussed further below. Most people are ordinary with the Yin/Yang symbol. However, one must first become acquainted with certain aspects of Chinese philosophy to comprehend its significance.
The symbol itself is a perfect circle divided into two equal but seemingly opposing halves that can represent anything from night and day, male and female, life and death. One half is black (Yin), meaning everything in nature that is negative, passive, feminine, or receiving. The white (Yang) half represents that which is positive, aggressive, masculine, or forceful. And within each half, a small circular section is the opposite color. The contrasting colors represent the two ends of a full spectrum. And the fact that each contains a little bit of the other is meant to convey the idea that nothing can be challenging or it will snap due to brittleness. Nothing can be utterly soft because it would fall apart. However, there is an innate Yin/Yang balance in all things in nature, and it is usually apparent which quality is more prevalent. While we categorize motions as Yin or Yang in nature in Wing Chun Gung Fu, we also strive to incorporate some qualities of both into every movement.
“Soft” vs. “Hard”—Just as everything in nature, from the smallest grain of sand to the highest mountain and beyond, can be analyzed in terms of Yin/Yang balance, the same concept of equal, opposing, yet complementary forces applies equally to the Wing Chun system’s many attacking and defending motions. This leads to the belief of “Yin and Yang Motions.” Yang or “Positive” activities catch the momentum of the torque on the side of the forward-moving shoulder and use its centrifugal force (the power of a spinning circle to throw objects off its surface) to push or impact the opponent. Yin or “Negative” motions on the retracting side that capitalize on centripetal force (the power of a spinning circle to draw inward as a whirlpool) have the opposite effect on the rival, pulling him in or “borrowing power” as they latch on to the “returning” power of the Power Arc.
One of the factors that Complex Motions are structurally attainable in Wing Chun is because of the Yin and Yang distribution of torquing power. As long as the student merges Yin and Yang motions on their correlating sides, he can perform a wide range of Complex Blocks, Attacks, and Double Motions, all of which rely on single pivots to power multiple simultaneous hands/or leg techniques.
The Arc of Power- To help visualize how the Concepts of Reference and Yin/Yang Motion interact, imagine that an “Arc of Power” is created whenever the stance is pivoted. Power converts from positive (Yang) to negative (Yin) at the Centerline during a stance pivot, as shown in Diagram HH. If there is no opponent, the Original Centerline is the reference point for determining this Yin to Yang conversion. In the first form, the Original Centerline was established. It is the ultimate point of positive power focus (like the apex of a golf swing) or damaging chambering (as in drawing a bow). As the stance is pivoted clockwise to the right from the Choh Ma position, any movement of the left arm originating from the left and traveling up to and including the Centerline on the Power Arc is said to be Yang in nature. Any proper arm movement that begins at or near the Centerline and moves backward along the Power Arc is considered a Yin, or “receiving” motion. As this fundamental concept is grasped, it will be clear that it is possible to create Yang motions with the right hand and Yin motions with the left in the same situation, depending on the origin and direction of the action.
As previously stated, the Arc of Power can be compared to a golf swing with a “Five-Iron,” with the point of maximum power release on the Centerline. Suppose a golfer places the ball on either side of the Centerline between his feet. In that case, he will hit it before or after his club has reached its maximum power point (the center) or after it has slowed down past the center on its way to a stop. In either case, his stance will be unbalanced as he reaches to either side to hit the ball. The Power Arc functions similarly. Because most Wing Chun techniques are aimed at our center, which is then aimed at the opponent, striking to either side of the center will not only throw the process off balance but will also cause the technique to land either before or after it has gathered its full strength at the Centerline. Any Yang technique that is not focused correctly on the Centerline will lose some of its lengths, as its structure requires it to reach its entire size and power precisely at the Centerline.
The Wing Chun student is taught early in his training to pivot his stance for added power. Stance pivoting, or Choh Ma, demonstrates to the student that a single torqueing motion generates a type of twisting force (Juen Ging) that radiates from every point on the Power Arc. This basically means that when the stance is pivoted, the torque created by the pivot is distributed evenly around the waist, chest, and back. One shoulder advances with the same momentum as the shoulder retracted by the same pivoting motion. Just as Yang motions must refer to the Centerline, Yin motions must refer to an exact point in space. That point is known as the Self-Centerline. As previously explained under the heading The Yin Cutting Angle, Yin motions must refer to a different point in space to have the same effect as their Yang counterparts. This is another example of how Wing Chun’s various combat theories overlap and work together to produce a single result. Complex motions like Gahng/Jom Sau or Tan Da rely on a single stance pivot to power two nearly simultaneous Yin/Yang motions.
The “merry-go-round” used by children in the park is a simple analogy. Suppose the merry-go-round is spinning, and two children simultaneously jump off. In that case, one from each side of its diameter will be thrown in one direction and the other in the opposite direction. Similarly, when the Wing Chun man performs a stance pivoting Tan Da, both his Tan Sau and his punch “jump off the merry-go-round” simultaneously. However, the Tan Sau will go in one direction (toward the Self-Centerline), and the energy will go in another (into the Centerline).
The student is introduced to the concept of “Reference,” which in its most basic context refers to the focus of an individual moving to a given point in space through a combination of certain Siu Leem Tau and Chum Kiu motions and the logic behind them. When the student first learns the Syeung Kuen (Double Punch) motion in the Siu Leem Tau form, he is taught to strike vertically with both sets of knuckles on the Original Centerline rather than with one fist stacked directly over the other. This leads to the realization that, even in a single punch, the “reference” to the Centerline should be the knuckle points rather than the middle of the fist. Although a hole is a Yang motion, the knuckles refer to the Self-Centerline because there is no stance pivot in the Siu Leem Tau form. Tan Sau and Woo Sau, as well as other Yang motions like Boang Sau and Jing Jyeung, fall into this category. The Centerline and Self-Centerline do not separate until the Choh Ma stance pivot in the Chum Kiu form, with the Tan and Woo remaining reference to the body and the punch remaining on the original Centerline.
Pock Sau, without a stance pivot, and again when pivoted, concerning the Centerline. Although the stance is not shifted, the Pock Sau slap block in the Siu Leem Tau form (photos A and B) references the past Center, subtly introducing the student to the principle of focusing Yang blocks to the Centerline when they are eventually executed with a stance pivot. This becomes clearer when Pock Sau is seen from above pivoted. Its body structure remains unchanged, with its reference fixed on the Original Centerline.
The Pock Sau slap block motion in Siu Leem Tau laid the groundwork for this concept; the Pock Sau motion originates at the Centerline and moves inward and forward past the line when executed in the form. However, the application focuses on the Centerline while maintaining the same relationship with the body as its non-pivoted form. When students understand the fundamental concept of reference, they can begin to execute the Siu Leem Tau techniques previously practiced in the stationary “Yee” Jee Keem Yeung Ma position, with various other forms of footwork beneath them. For example, the same straight punch described above could be carried out with Choh Ma footwork, which adds torque and slightly changes the angle of the point but does not change the reference.
In other words, when you turn with a punch, the knuckles of the punching hand should land precisely where they would have if you hadn’t pivoted, except for a slight increase in the length of the punch. If you swing and punch again on the opposite side, the knuckles of the opposite hand will occupy the same point in space. The pivoting effectiveness at the start of the Chum Kiu form introduces this to the Wing Chun student. Except for the pivoted stance, this punch is identical to the first punch of the Siu Leem Tau form. Its reference point (the Centerline) remains the same. However, the body now faces 45° outward, and the punch becomes slightly longer and more powerful. The Choh Ma Boang Sau motion also introduced the concept of Yang blocks remaining referenced to the Centerline even when pivoted in the Chum Kiu form. When you practice the form in front of a mirror, you will notice that you are being shown to block the same punch thrown earlier in the state with a Yang block focused on the same point in space as that punch.
The Choh Ma Lon Sau demonstrates how a Yin block remains referenced to your own body, as it did in Siu Leem Tau. In contrast, Yang motions such as the punch and the Boang Sau remain referenced to the same point on the floor that they did in Siu Leem Tau. As a result, the Chum Kiu level student will realize that the Centerline viewed at Siu Leem Tau level was made up of two lines that happened to overlap because you were pivoted to the exact Center. However, as you began to shift, you noticed that the line splits into two—the one that remains “painted” on your body (the Self-Centerline) and moves with you as you move, and the one that remains “painted” on the floor (the Centerline).