The following is an excerpt from the book Taekwondo: The Spirit of Korea (2000) by Steven D. Carpener, Jae Sik Suh and Edward H. Kim, from the chapter "The Technical Philosophy of Taekwondo" (p. 23-25). I'm sharing this excerpt as it very effectively explains the very important Princple of Full and Empty Space. Interestingly, while this book was published by Korea's Ministry of Culture and Tourism as a type of glossy coffee table book rather than an official reference book, this is one of the few English sources that so succinctly explains this core principle in Taekwondo.
. . .
Taekwondo's Taoist philosophy is expressed in the Tao (or Do in Korean) character found in taekwondo's name. The Do is generally understood as a way, path, or process one follows in anything one attempts. Do, as an Eastern philosophical concept is difficult to express in words. However, in describing taekwondo training it is possible to demonstrate how the Do elevates taekwondo from merely a spirited combat sport or self-defense technique to a way of expressing harmony between one's mental and physical states, and with one's environment.
The way the Do operates in taekwondo training must be understood in Asian philosophical terms. The general understanding of the Do is that it is a proper way to do something. In physical terms, this means when the body moves there is a proper way or path which that movement should follow to be most efficient, graceful, or appropriate. In taekwondo training, especially in sparring, this means that there is one most correct way to execute techniques in any given situation. This is the stage of skill. When one teaches a point where the body moves naturally according to the proper way or path, we say that one has mastered a particular skill. In taekwondo sparring, when one's movements are performed correctly according to the demands of the situation, one has experienced a moment of harmony between oneself and the opponent.
One of the key principles of the Do that makes this harmony possible is the principle of empty and full space. According to this principle, when two bodies interacts, the relative positions of those bodies in space and time create a continuous flowing exchange of full and empty space. Due to the limited number of ways the legs and arms can be used within the restrictions (rules) of sparring there are a fixed number of possible techniques. The result of this is that for every attack there are one or more perfectly complimentary counterattacks. And for every counterattack, there are one or more perfectly complimentary re-counterattacks. This means that each person knows what the likely responses to any given attack or counterattack will be. Therefore, the superior player is the one who can take advantage of the empty space created in the opponent's position by using speed, timing, and strategy.The strategic aspect of taekwondo is especially fascinating. No other martial art uses kicking techniques with such finesse and accuracy. The superior player's body is able to predict or sense the moment when his or her opponent will surrender an instant of empty space which, if “filled” with the appropriate technique, results in a scoring strike that has the symmetry of two perfectly meshing gears. This moment, when a point is achieved by manipulating the principle of full and empty space, is not only the goal of sparring and competition, but can also be a moment of physical and mental harmony: the harmony of one's own spirit and body resulting in right action, and the harmony of one's fullness with the opponent's emptiness.
When approached in this way, taekwondo sparring is ripe with the potential for philosophical (educational) value. The moment of right action is very important not only in the sense that one's technique and spirit are correct but also because this is the instant when one has entered the level of the Do. It is the ultimate moment when one's body has found the way to fill the opponent's emptiness in the midst of fierce resistance. When one repeatedly experiences this harmony, the doors to higher understanding can be flung open. In fact, it may seem as if the secrets of the universe are being revealed through these quick, precise movements. The taekwondo practitioner then comes to see the opponent not as an adversary but rather, as the potential medium for creating a work of art, much as the sculptor does not merely see a piece of stone but, rather the creation waiting to be liberated.
Just as there is a technical or physical aesthetic in taekwondo, so also is there a spiritual aesthetic. In order to teach the level where one's techniques and movements approach the ideal, a great deal of training is needed. This training is a process which brings about mental and spiritual change.
. . .
The authentic practitioner understands that taekwondo is a way, a process, and not just a means to an end such as fighting skill or medals. This is the paradox of the Do; the authentic practitioner who values the internal process of development more than external rewards usually develops the best skills.
