The technique Double Closure is first recorded in the form Peach Thieving (Bai Yuan Tou Tiao, lit. peach thieving by a white gibbon). It is the first movement of the form, while at the same time, the ending movement in other forms within the Mantis School, including those in the the Six Harmonies style.
The name of the school, Mantis, is taken after this technique, for it looks like the arms of a praying mantis in its performance. That said, the technique is not meant to be performed on its own in the air, and it is not to imitate the praying mantis: the movement is used to read and control the opponent’s movements. This reading is not static, one has to exert pressure on the contact points on the wrists in the manner of a whirlpool to ask for the opponent’s resistance.
The simplest interpretation of the Double Closure is using the controlling methods of ladle (diao) or hook (gou, not to be confused with a hook punch) to control the opponent’s wrists. Ladle and hook are very similar, and it is not helpful to give them clear distinction for their applications, as which one to use is entire contextual. Yet, in the attempt to further our discussion with a common parlance, we can say that a ladle is the method of control of the opponent’s wrist using the thumb and either index or middle finger in the manner of an elastic band, whereas, a hook is to control the opponent’s wrist by hooking your own wrist without a tight grab.
Both ladle and hook start with sliding your arms from the opponent’s elbow, and ending with a control position of the wrist in a circular motion. These movements can be performed from either outside or inside lines, and the form Peach Thieving gives us the directions from the outside.
The form Crushing Steps (Beng Bu) describes a variation with one arm in the inside and one outside. Another interpretation with the same move in the same form is with both arms go from one side, this is then called Pouncing (Pu Chan) or Double Catch (Shuang Cai). The movement can also start by having both arms from the inside, but instead of doing the ladle or hook, it is better to flip your hands inside out so the palms face up and outwards: this move is a redirection of the opponent’s pressure and a setup for attack at the same time.
As discussed above, there are many names to describe the same technique in different forms, and it is important to note that the names are simply there to record the however slight variations, but the core concept remains the same. The technique of Double Closure is not to tell you how to attack or defence, as that would be a very superficial description. Instead, the Double Closure, as one of the core concepts of the Mantis School, is to describe how the two sides in the act of fighting would form an imaginary sphere between their chests, with application the conflicting force (pressure and counter-pressure), whether and how to attack, defence, or counter-attack depend entirely on which direction the sphere rolls.
The sphere can roll forward and backward, up and down, left and right (these would be the so-called Six Harmonies in terms of direction), horizontally, vertically, or diagonally, and with the staggering movements, i.e. the movements of Ying Yang, these rolling directions would tell you where the gaps are, so that you would know where and when to attack and counter in a continuous flow.
The New Treatise on Military Efficiency (Ji Xiao Xin Shu) of 16th century gives us some principles or proverbs on martial arts, such as “an attempt in parring will receive a punishment of ten hits in return”, “to impose on the enemy, but not to be imposed by him”, “wait till the previous force has just passed and hit while a new force has yet to generate” etc., can only be achieved with the idea of the sphere with conflicting force. Once this idea is thoroughly understood, whichever school you are from and whichever technique you are going to use and call will no longer be a matter.
To learn the technique of the Double Closure, one can use the movements to control the central line and shake the opponent’s balance slightly, with your wrists sticking on top of his wrists. If his body leans forward, you can pull back and thrust his eyes; if his body pulls backward, you can lean forward to thrust his eyes. This called the eye thrust, but note that it does not matter if you can injury his eyes, as it is also a movement to force your opponent into defence, which gives you the opportunity to impose your will.
In the attempt to open the opponent up from the inside, you can also thrust his face, and when he parries outside-in, you can follow his force and perform a hook punch in the manner of a leak, If he dodges the hook, you can then follow and perform a back fist. If he dodges the back fist, you can follow by a punch to the stomach with your other hand. If he can parry this one, then you can again leak and perform another hook punch. The flow does not stop. The above techniques are detailed as the first three movements of the Peach Thieving form, and the ideas behind are very simple: Double Closure, Thrust, and Leak. Other variations depend entirely on the opponent’s movement and resistance, and it is impossible to describe them all here.