One of my most treasured kendo possessions is a piece of calligraphy, given to me by the late Matsumoto Toshio sensei, kyudan. The characters simply say ken ri, which to my meagre understanding translates as sword reason or theory.
This was the cornerstone of Matsumoto sensei’s teaching and means that there is a reason for any action we make in kendo. At the time I received it, as a 4th dan in my twenties, it seemed logical if slightly esoteric, but only now as my kendo has matured over the years; does it really start to make sense on a physical level.
When I read the depth of analysis of kendo theory that regularly appears in the various kendo forums, I am amazed at how knowledgeable many relatively new kendoka appear to be about complex concepts. The question, however that is often in the back of my mind is, are they actually able to manifest these theories in their keiko.
I suspect that I may be intellectually lacking, but it is only after I have practiced something continually for years that it starts to make sense on a practical level. For example most forms of seme can only be successfully introduced into your kendo practice if you are completely familiar with the waza that you need to back them up. Irrashai or sasoi no seme where you invite your opponent to attack, is basically a way to allow your opponent to hit you. That is unless you have complete mastery of debana or kaeshi waza or whichever other technique you need to take advantage of his or her movement. So in my view, you need to understand the theory, but more importantly you need to be able to put that theory instinctively into practice, without thinking.
Ken ri is obviously discernable in kendo no kata when it is practiced at the highest level. The difference between going through the motions of kata by numbers and watching the mastery of action and reaction or riai demonstrated by kendo meijin is immense.
Whilst I am still in no position to best guess Matsumoto sensei’s thoughts, I am pretty certain that he was talking about reason when it is understood by the mind and body.