Applied theory

In the last post on the site I discussed about what the term ji-ri-itchi means to me personally on a more macro level, and now I want to discuss a particular example of a theory applied to physical practise.

Ken-chu-tai, tai-chu-ken

AFAIK the first reference to the teaching of Ken-Tai appears in Yagyu-shinkage ryu’s Hyoho Kadensho, written by Yagyu Munenori in 1632 (it also appears in Hozo-in ryu and Itto-ryu documents, and probably more traditions as well). Ken-tai and variants of it (e.g. Kobo-fuki, Do-sei-ichinyo, etc) are usually rendered into English as “defense within attack, attack within defense” or more simply as “attack and defense as one. A description from the Hyoho Kandensho reads:

“Ken means to attack single-mindedly, to strike fiercely in order to be the first to strike a blow.

Tai means resisting making the initial technique while awaiting the opponent’s first move. It must be understood that tai is a position of utmost watchfulness.

Ken and tai mean to attack and wait.

Concerning the principles of ken-tai pertaining to the body and the sword, advance upon the opponent with an attacking posture and hold the sword in a position of waiting, making efforts to entice the opponent to make an attack and counter it. In this way ones posture is in an attitude of ken and the sword one of tai. The ken posture is used to induce the opponent to initiate the attack.

Ken-tai pertaining to the mind and body. The mind should retain an attitude of tai and the body an attitude of ken; this is because if the mind retains an attitude of ken it races and this is not good; thus have the mind wait in tai, and with the body in ken induce the opponent to make the first move and defeat him.

Again there is the principle whereby the mind takes an attitude of ken and the body in one of tai; the reason for this is that with the mind in ken it is put upon its guard and with the sword in tai the opponent is induced into making the first attack. One should think of the body as being the hand that holds the sword. Thus the mind takes the attitude of ken and the body one of tai.

Ultimately both methods are the same, the aim is to induce the opponent to make the first move and defeat him.”

Kendo Tokuhon (The Kendo Reader),, October 2013

I don’t think the theory of Ken-Tai is particularly difficult to understand cerebrally, but utilising it effectively within keiko is another matter. Specifically, I’d like to talk about it in reference to executing oji-waza.

I’ve sometimes seen oji-waza described as “reactive” techniques in English but I posit that this is – for advanced practitioners anyway – a misnomer. I mention this in my Kendo Coaching Tips and Drills under the “Oji-waza is not a guessing game” section. To be clear (under this definition): oji-waza are techniques executed with prior knowledge to what your opponent is going to do. The reason you have this foresight is that you have setup the situation: that is, you are in control of not only the area being struck, but also the timing.

A specific example: men-kaeshi-dou

To setup the situation you need to do two things:

1. Open up your men for attack;
2. Seem to be unaware of the impending attack.

There are many ways to open your men up, but the easiest one is done simply by dropping the point of your shinai down diagonally to the right (preferably subtly) and, at the same time, moving your right foot out diagonally (body in ken). By doing this all you need do is raise up your arms to catch your opponents men strike and move smoothly into the dou strike. Needless to say, you should be calmly watching your opponent and calculating while doing this (mind in tai).

However, we still have a problem. If your fighting spirit is obvious and/or your look like you are setting things up, then your opponent will not attack you (unless they are inexperienced): you have to fool them into actually believing that you are actually open. If you are overtly obvious in your setup or desire to strike then experienced people will not strike.

In this situation it’s often best to make your attacking spirit obvious immediately prior to the setup described above… then slightly relax the pressure. The switch from overt pressure to a relaxing of it is often enough for someone to launch an attack… inexperienced people will attack at this point even when there are no openings. This, of course, is Ken-tai in application.

Do I need to know the theory behind the action?

The answer to this is “no” if you are doing kendo casually, and “yes” if you are not. To some extent, “knowledge” of kendo will come naturally through doing it… in fact, I suspect that the best and most naturally way of understanding kendo is simply through constant daily practise without too much thinking. At some point, however, especially if you want to become a teacher, then it’s probably better if you spend time on the whys and wherefores.

Many people might say “I can describe my experience without relation to the more traditional kendo terms” which I think is a fair comment. I guess it’s up to the individual to choose how they teach and describe kendo. For me personally, I prefer to pepper the description with classical terminology…. kendo is after all, for me anyway, also a study of the past.

There are a number of overlapping theories used to describe the physical and mental process of executing kendo techniques, for example the different kinds of sen, discussion of kyojitsu (a term almost unknown in the English kendo community and disappearing in the Japanese one), and various other teachings from classical swordsmanship schools that have found their way into kendo theory. On top of this there is also the more modern boxing of waza into shikake and oji techniques, the odd sports-science explanation, and of course personal theories (sometimes eccentric) from various teachers. Some of these complement each other (for example, my use of ken-tai to describe oji-waza), and some don’t (the various types of sen and the shikake/oji waza definition).

I guess the point here is that for every action you do in kendo has, theoretically, some sort of rationale behind it, and if you want to be a good kendo teacher then you should spend time not only in research of these theories, but in actually application of them. At least, this is my aim.

“An important teaching, comprehension is difficult to come by without hard training.”

For a longer discussion on Ken-Tai, please see p84-6 of the kenshi 24/7 published Kendo Tokuhon (The Kendo Reader). Also, don’t forget to check out Kendo Coaching Tips and Drills for discussion and description of oji-waza.

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I'm the founder and chief editor of Amongst other things I am a high school kendo club coach, an avid practitioner of classical swordsmanship, a history student, and a vegetarian.

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