This following is Part 2 of Marshal Yue, Fei's "Ten Important Theses," which includes Theses No. 2 through No. 4.

2. Thesis of Yin and Yang (Yin Yang Lun)

It is seldom heard that he who discusses striking, also discussed Qi. About the Qi, it is mastered as one but can be divided into two. What are these two? They are inhaling and exhaling. The inhalation and exhalation are the Yin and Yang. The striking cannot (be done) without moving and calmness. The Qi cannot (exist) without inhaling and exhaling. Inhalation is Yin and exhalation is Yang. The one, which is calm, is Yin and the one, which is moving, is Yang. Raising up is Yang and sinking downward is Yin. When Yang Qi is rising up it becomes Yang, and when Yang Qi is being transported downward it becomes Yin. When Yin Qi is being transported downward it becomes Yin, and when Yin Qi is being transported upward it becomes Yang. This is the discrimination of Yin and Yang.

At the time when Yue, Fei was writing these theses, few martial artists were using Qigong to improve their martial abilities. Qi can energize the muscles to reach their maximum potential, and it can also raise the spirit of vitality to a higher level. Through Qi you can be calm, and through Qi you can be excited. Through the behavior or action of Qi, your emotional state, thinking, and movements can be distinguished into Yin and Yang.

Generally, Yin is the seed of Yang and Yang is the blossom of Yin. Yin is for storage and Yang is for manifestation. Yin is sunken and Yang is raised. Yin is steady and calm and Yang is excited and powerful. All of these manifestations of Yin and Yang are generated through inhalation and exhalation. Inhalation and exhalation are considered the strategy in Chinese Qigong. Proper inhalation and exhalation techniques can adjust the Yin and Yang of the body. Therefore, to be a proficient martial artist you must know these two strategies for controlling the state of your body.

What is meant (by) clean and muddy? The one that rises up to the top is clean and the one descending downward is muddy. The clean Qi rises upward and the dirty Qi sinks downward. The clean one is Yang and the dirty one is Yin. The important (thing) is that Yang should be used to nourish Yin. Generally speaking, they (i.e., Yin and Yang Qi) are united as (one) Qi, if divided, they are distinguished as Yin and Yang. Qi cannot be without Yin and Yang, and it is just like man cannot be (alive) without having movement and calmness, the nose cannot be without inhalation and exhalation, and the mouth cannot be (with) no exiting and entering. This is the unchangeable theory of natural cycling. However, though Qi can be divided into two, in fact, it is one. Those who like to study this should be careful not to restrict this (theory).

In order to make your mind calm so that you can think clearly, you must sink your "muddy" Qi to the Lower Dan Tian. This refers to the Fire Qi, which can make your body too Yang and your mind overexcited, unstable, unclear, and confused. Clean Qi refers to Water Qi, which makes your body Yin and calms down emotional confusion. This makes it possible for your judgment to be accurate and neutral. This seems to indicate that Yin and Yang are two distinct things, but, in fact, Yin and Yang cannot be separated. Yin is the root and the seed of Yang, but it also needs Yang to nourish it so it can grow. Without the nourishment of Yang, Yin will not grow and gradually derive into Yang. Out of Yang is produced the seed (Yin). Also, without Yin, the Yang will have nothing to grow from.
Although Qi can be divided into Yin and Yang states, in fact, there is only one kind of Qi. Yin and Yang are the result of the manifestation of Qi in the body. If you are bound and restricted by this theory, then it is dead and not alive. The fact is, Yin and Yang are relative, not absolute. This is important for you to realize if you want to understand Yin-Yang theory and apply it properly.

3. Thesis of the Three Sections (San Jie Lun)

Qi is the root of the entire body and the sections of the body do not have definite places/positions. What are called the "three sections" are the top, middle, and bottom. For the body, the head is the top section, the body is the middle section, and the legs are the bottom section. If (we) talk about (only) the top section, then the crown is the top section, the nose is the middle section, and the tongue (Haidi) is the bottom section. If (we) talk about the middle section, then the chest is the top section, the abdomen is the middle section, and the Dan Tian is the bottom section. If (we) talk about the bottom section, the feet are the ending section, the knees are the middle section, and the hips are the root section. If (we) talk about the arms, the hands are the ending section, the elbows are the middle section, and the shoulders are the root section. If (we) talk about the hands, the fingers are the ending section, the palms are the middle section, and the roots of the palms (i.e., near wrists) are the root section. From this, (we) do not have to talk more about feet (i.e., give more examples).

If you look at your body from the point of view of Qi, the body should not be divided. This is because the Qi in the body is continuous and threaded together into one. However, if you look at your body from the physical perspective, then you can divide it into three sections in many different ways. This is done solely for the convenience of discussion. Other than this, however, your mind should not be restricted by these divisions. Your body should act as a unit, and should not be broken into parts. Haidi means "sea bottom" which implies the tongue.

However, from the head to the feet, all have three sections. The important (point) is that if there is not a distinguishing into three sections, then the meaning cannot be clear. Because (if) the top section is not clear, there is no dependence and no origin. (If) the middle section is not clear, then the entire body is void. (If) the bottom section is not clear, then you will fall by yourself. How can we ignore them? As to how the Qi starts to move, there is nothing but the end section must move, the middle section follows, and the root section urges. However, all of these discussions are because (we) divide (the body) into sections and talk about them. If we talk about when they are all combined, then from the top of the head to the bottom of the feet, the four limbs and hundreds of bones, all in one section, how can they be divided into three sections? Furthermore, how can we again divide each section of these three sections into another three sections?

There are many ways to divide your body into three sections. The sole purpose for this is to make the meaning clear. For example, if the head (top section) is not clear, then your thinking will not be clear and ideas will not be generated. Ideas are the main motivation of movement. If the chest and the waist (middle section) are not clearly connected to the head (top section) and to the legs (bottom section), then this center portion of the body will be missing, and the body will lose the physical center of its movements. Finally, if you do not have a clear understanding of the meaning (i.e., purpose and function) of the legs, then you will lose your root and foundation, and even though you have a clear idea of what you want to do and can control your torso, your movements will not be smooth and efficient.

For each movement, the secret of starting the Qi is your Yi. When your Yi generates the idea for a movement, the Qi will be led immediately to the end section. This starts the movement of the end section. The middle section naturally follows, and the root section urges the movement. This concept is different from how Jin is manifested in Taijiquan. In Taijiquan, Jin is generated first in the root section, directed by the middle section, and finally manifested in the end section. The reason for this difference is that in Taijiquan the body is like a whip, soft and very relaxed. When the mind generates an idea, the legs first generate the power (shoulder), the power is directed by the waist (wrist), and manifested in the fingers (tip of the whip). However, in Xingyiquan, the body acts like rattan. Though flexible, it is still hard. Therefore, when the Yi is generated on the target, the tip can move first, and the power is pushed from the body and the root section.

4. Thesis of the Four Extremities (Si Shao Lun)

(Now let us) try, in addition to discussing the body and the Qi, to discuss the extremities. The extremities are the surplus ends of the body. Those who talk about the body have never mentioned these since the beginning, and those who talk about the Qi have also seldom discussed them. Striking is (generated) from the internal and emitted to the outside, and thus the Qi is (generated) from the body and reaches to the extremities. Therefore, (if) the application of Qi does not originate from the body, then (this application) is void and not solid. (If the application of Qi) does not manifest in every extremity, though solid, it is still void. How can (we) not talk about the extremities? However, (we have mentioned) only the extremities of the physical body and have not mentioned the extremities of the Qi.

The four extremities are not the limbs, which is what one would ordinarily think. Instead they are the hair, the tongue, the nails, and the teeth. Chinese doctors frequently diagnose patients by examining the condition of these extremities. Chinese medicine and Qigong believe that these four extremities will be healthy only when your Qi is circulating smoothly and properly in your body. Therefore, in Xingyiquan it is believed that you should learn how to lead the Qi to them.

What are the four extremities? The hair is one. Because the hair does not belong to one of the Five Phases and is not related to the four limbs, it seems that (it) is not worth discussing. However, the hair is the ending of the blood and the blood is the ocean of Qi. Even though we do not use the hair to discuss Qi, (we still) cannot ignore the blood (when we discuss) the generation of Qi. (If we) cannot ignore the blood, then (we) cannot but also be concerned with the hair. (When) the hair is (strong enough) to shoot up the hat, (the Qi) in the blood ending is sufficient. Others such as the tongue is the ending of the meat (muscles) and the meat is the Qi bag (i.e., capable of storing Qi). (If) the Qi cannot be manifested in the ending of the meat, then there is not enough quantity of Qi to fill up (the muscles). Therefore, the tongue should urge (i.e., push against) the teeth, then (the Qi) in the meat ending will be enough.

The first extremity is the hair. According to Chinese medicine, the hair is closely related to the blood, which is a carrier of Qi. The blood cells need Qi in order to function. They also, act like batteries and store Qi, releasing it to the parts of the body that require it. When your blood cells are healthy and are able to store an abundance of Qi, they will carry Qi to the surface of your skin and stimulate hair growth. When your spirit is excited, this Qi will give the hair an electrical charge, and it will stand up like a cat's does when it is excited.

In the same way, the tongue is considered to have a close connection with the muscles. Muscles are like a storage bag for Qi. When you exercise the same muscle repeatedly, the Qi and blood will gather in that muscle. When you relax after finishing your exercise, the stored Qi will be released to the outside or will re-enter the Qi channels in the body. Since the tongue is the ending or extremity of the muscles, if you are able to lead Qi to the tongue, surely you have already effectively led Qi to the muscles.

As to the ending of the bones, it is the teeth. The ending of the tendons is the nails. Qi is generated from the bones, which are connected to the tendons. (If the Qi) cannot reach the teeth, it means (the Qi) cannot reach the ending of the tendons (either). (If you) desire to have plenty (of Qi), then it cannot be done unless (your) teeth are able to break the tendons and the nails are able to penetrate the bones. If (you) are able to do this, (then the Qi) of the four extremities is sufficient. When (the Qi) of the four extremities is sufficient, the Qi (in your body) will be plenty automatically. In this case, how can it be still void (i.e., the Qi be deficient) and not solid (i.e., the physical body not be strong), or though solid still void?

Qi has to fill the whole body. If you try to make each ending stronger than the others, you will end up strengthening them all equally, and your whole body will be strong. In this case, how could you have abundant Qi and not have a strong body?