Author: Bret Gordon
Few things in the martial arts have caused more controversy than the discussion of aiki. The general public, and majority of the martial arts community, dismisses aiki as some form of mystical "chi" power akin to the "no-touch knockouts" of George Dillman (with just as much effectiveness). Even those in the aiki arts, however, struggle to come to a consensus of what aiki is... And they're the ones that teach it! In this article, I'll attempt to break through the shroud of mystery and disinformation (more on that later) surrounding the world of aiki. Let me apologize now, as this won't be a quick read.
In order to understand what aiki is, we first must translate it into laymen's terms. The kanji which comprise it, 合気, are often translated as "harmonizing energy," but of course that doesn't say a whole lot. The first character, 合, is itself three kanji: 人 (person), 一 (one), and 口 (mouth). One of the best breakdowns I've heard for this character is "two people speaking through one mouth," referring to the instant that two opposing forces come together. This is also the inspiration for the Taiji (often called the yinyang or inyo symbol). It is not two objects crashing into and destroying each other, but rather dual opposing spirals whose paths intertwine.
The second character, 気, is the simplified version of 氣, which is essentially a drawing of boiling rice. "Where the translation of Ki as energy comes from is the fact that the energy from the fire below the stove boils the water which produces energy from the steam. This type of combustion is the basis for steam engines. However, it is not just the energy that causes the lid of the pot to lift. It is the relationship between the fire, the stove, the pot, the water, the steam, and the lid that makes it all work together. To this end, Ki is best translated as 'relationship' as opposed to 'energy.'"
Of course, defining the kanji doesn't get us any closer to understanding what aiki actually is. The truth is that there are several definitions, which in their own respective context are all correct due to their interpretation of the kanji themselves. We first see "aiki" as a concept in sword arts. It is described as a specific phenomenon, a moment in time that requires perfect timing and precision. It is achieved through superior knowledge of strategy, tactics and potential threats.
In an article published on Aikido Journal, Ellis Amdur writes, "One place we see this is in kenjutsu, and an exemplar of it is in Itto-ryu (remember the deep ties that Itto-ryu has with Daito-ryu). As the enemy cuts, so, too, do I cut. Not “along” the same path. ON THE SAME PATH. Two objects cannot occupy the same space, and I, with greater power/speed/timing/postural stability, etc, take that space. The enemy is, ostensibly, deflected, but they are NOT knocked away. They are simply not allowed to occupy that space. And often there is no tai-sabaki (body displacement, getting off line). There might be. If there is, it is simultaneous—not one following the other. But even beyond that, tai-sabaki is not part of the fundamental definition of irimi, simply an elaboration of it."
While Amdur sensei is describing the principle of Irimi (entering), that instant when two opposing forces come together and intertwine is an expression of aiki. It's this definition of aiki that is so prevalent in modern Aikido, where the focus is on blending with the opponent's force and leading them to their eventual downfall. It's focused on that moment in time when uke ceases to become a separate entity from tori/nage.
However, modern Aikido students using this understanding of aiki often find themselves chasing the skills and power of Aikido founder, Ueshiba Morihei, to no avail. That is because Ueshiba functioned using another understanding and interpretation entirely, one he learned during his time in Daito Ryu, and one which the majority of high-level "internal" practitioners all share.
Sagawa Yukiyoshi, often considered the most skilled and advanced practitioner of the aiki arts after Takeda Sokaku himself, often spoke of what he called Aiki no Rentai 合気之錬体, the conditioned aiki body. The aiki body is a pre-conditioned state of being, that through vigorous training and solo exercises has been rewired in how one moves, carries and transfers weight, absorbs and expresses force, and even stands. While the process of cultivating the aiki body is rather complex and requires a deep anatomical understanding, I will briefly scratch the surface here.
In order to move any part of your body, you must first fire-up specific muscle groups. Most practitioners of external martial arts create power by engaging large muscle groups and generating torque through rotation. Those with an aiki body do so by engaging the deeper tissue, using the myofascial meridians as a roadmap to how the body is ultimately connected.
Once you learn to engage the connective tissue, you can begin to receive, process, and return force along these meridians. By treating the body as a single, cohesive unit rather than simply a torso with multiple independent limbs, everything becomes powered by the entire body. A term often used to describe this phenomenon is cross-body connection. A simple description of cross-body connection is if I was to throw a right straight punch, rather than simply pivoting on my right foot and rotating my right hip, I would first pull the left side of my body back to propel the right arm forward. By changing the origin of movement, the force isn't isolated to the attacking the limb and instead is generated with the entire body.
In the study of internal martial arts, you may hear the term "Six Harmonies." This is a concept originally derived from Taijiquan, it actually teaches how to create the aiki body. The Six Harmonies (three external, three internal) are as follows:
The three external harmonies describe how to move the body as a cohesive unit to express coordinated power (集中力 shuchu ryoku). The three internal harmonies describe the relationship between your intent and your actual, physical movement. Of course, the aiki body involves much more than simply having a connected structure. Entire books have been written on the subject, so I won't pretend to do it justice in this single article, but hopefully you start to get the picture.
Stay tuned for part 2...
 Duplantis, Fr. Daniel. Jesus In The Dojo: A Christian Pedagogy of Martial Arts, p. 100-101