Kirby, George. Jujitsu: Advanced Techniques for Redirecting an Opponent’s Energy. California: Black Belt Books, 2015.
From the title, it sounds like George Kirby and his jujitsu borrowed some pointers from aikido. Aikido techniques are derived from jujitsu, so are some of its concepts. Aikido may be characterized as soft and jujitsu as hard, but these two arts are two sides of the same coin. Kirby demonstrates this concept throughout his book, as the most efficient way to overcome an adversary is to redirect and utilize the energy given by him to one’s own advantage, while conserving one’s own energy. Kirby lays the foundation of his book with three key concepts, which creates a triangle, which, according to Kirby, allows the practitioner to form “a firm geometric base […] on which to build [a] structure.” One concept is tachi waza (balance), another is kuzushi (breaking balance), and the final concept is ki (energy). It is then a combination of these three concepts that a jujitsuka can fully utilize their adversary’s energy by redirection.
To efficiently redirect a person’s energy for a practitioner’s own use and advantage, the practitioner must understand balance in relation to both one’s self and to another person. Since balance originates from a properly structured posture and stance, it is important, as Kirby explains, to have the body aligned horizontally, vertically, and rotational (Kirby defines these as x-axis, y-axis, and z-axis respectively). Kirby also stresses the importance for a practitioner to have balance throughout movement, which results in how well the opponent is off balanced and how well a practitioner can execute a technique.
The opposite of balance is imbalance, or kuzushi. To break an opponent’s balance, one must first redirect their energy to one’s own advantage. Kirby breaks down kuzushi into two categories: the physical off-balancing and the psychological off-balancing. He explains that one can physically off balance an opponent by blocking or parrying the opponent’s strike, redirecting their energy to assist in whatever technique one chooses at that moment. In addition to this redirection, one can supplement the redirection of energy with a strike of one’s own, further off balancing the opponent. In the psychological sense, one can distract a would-be opponent by bringing their attention to something else, be it an object on a building or something farther away and behind the opponent. This psychological off-balancing brings the opponent’s attention away from the would-be victim, allowing the latter to utilize both of the opponent’s off-balance and energy to the latter’s advantage.
The concept that penetrates through tachi waza and kuzushi is ki, or energy. Ki is thus the energy that both the defender and opponent use to gain the advantage over one another. Kirby explains, however, that it is not the possession and usage of great energy that ultimately overcomes an opponent, rather, it is the efficient, effective, and proper usage of energy. He then proposes the question, “Why use all of your energy when you can use some of your opponent’s?” The answer comes in the combination of kuzushi and of tachi waza, as mentioned previously. If a practitioner is properly structured and balanced, as Kirby explains, a practitioner can then redirect an opponent’s energy just enough to break their balance, just enough for the defender to throw, takedown, or control the opponent. From this statement, a practitioner cannot have effective and efficient kuzushi without being properly grounded and proficiently redirecting and using an opponent’s energy – all three become part of the triangle as Kirby described. It is from this trio of concepts that a practitioner can utilize an opponent’s energy in a dynamic scale of large and small movements.
In the end, Kirby did not make a manual solely for jujitsu. Yes, the title has the name jujitsu in big black letters at the top of the cover, but the concepts and information can help more than just jujitsu practitioners. His manual can help those studying aikido, judo, and other grappling-based martial arts. Throughout his book, Kirby demonstrated that jujitsu can be just as soft as aikido but can also be hard when need be. To say that a set of concepts, principles, and ideas only belong to one martial art seems a bit biased. Every martial art is a study of body mechanics and manuals like Kirby’s help drive the idea that concepts and principles are similar, if not the same, across many different martial arts.
 George Kirby, Jujitsu: Advanced Techniques for Redirecting an Opponent’s Energy (California: Black Belt Books, 2015), 71.
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