This principle taken directly from kenjutsu, states that attack and defence must be applied in the same instant. Example: entering off the line of attack while executing a strike yourself.
Below is a perfect example of this showing O'Sensei entering on Tamura shihans thrust. Again it is the sword principle of "attack at all times" even when you yourself are under attack.
This damashi or fighting spirit tends to be difficult for those who "cling" to a pacifist philosophy during conflict.
The true attitude is that we must not fight or instigate conflict but when forced to we must end the conflict as quickly and effectively as possible.
Ken Sen - Control of the Centreline
During training we must strive to execute techniques without presenting an opening for a strike or a counter. To do this we must control the centreline i.e. attack him while defending our own centre. If we enter to the side to execute kote gaeshi, we must atemi with the free hand to attack his centre while simultaneously defending our own (if he is defending the atemi he is not attacking). Also the wrist must be turned in such a way that it affects the elbow which effects the shoulder which displaces the hip. This is a subtle angle and of course attacks the kuzushi.
Basic Sen is to see an attack coming and move out of the line of attack and counter with a technique or atemi. Sen No Sen is to see an attack coming and to intercept it redirecting the energy to facilitate a technique. Sen Sen No Sen is to see a suki (opening or opportunity) and to enter and make a technique before the attacker can respond. All these principles have one thing in common - the breaking of the rhythm.
Ki to me means attitude and fighting spirit. Since I believe that he with the superior attitude has an advantage, I have no problem when someone says he has a stronger ki. "Catch his intention to strike" can be interpreted as catch his ki.
However, all of these principles can only be practised if there is a sense of danger and their application accompanied with pragmatic and effective technique. There should be no mystical connotations.
Kokyu nage - timing, unbalancing and spirit - no mystical connotations.
The instant you "touch the sword". When you sense danger you must "fill yourself with the intent to cut down the opponent". This and nothing more.
When we come under threat the mind may become vulnerable to what in Budo are called "sicknesses". Fear, confusion, hesitation, even anger or carelessness.
The term "fill yourself" rather than fill the mind. Advises that you should have only one thought and that is attack. There is no pre-conceived strategy or technique, the belief being that the attack and action are instantaneous. Both the fighting spirit and the body must be "relaxed but alert".
Basic principles of moving off line and inside the line of attack should be trained time and again until they become as instinctive as possible.
Attack at all times leaving no openings in timing or distancing that the opponent may use. Destroy his will to continue.
This is the mindset of self defence. There is only an explosive attack with no thought of defence or danger, simply an application of fundamental principles as swiftly and powerfully as possible.
This is most difficult to apply in a competitive manner as no competition is to be allowed to the opponent. If two experienced martial artists should compete in such a manner both are most likely to be injured. The outcome of a real confrontation is decided in the first few moments.
"The techniques are too deadly for competitive arts". I have no time at all for such remarks, too often they are spoken by those who have never competed or trained against resisting opponents. I would encourage everyone to crosstrain in a competitive art simply for the experience and to gain the respect for that art which I assure you will follow.
Nor do I believe that one trained only in a competitive environment shall retain the competitive mind. I believe that they shall instinctively let go of all and any inhibitions when under a real threat.
Attack at all times is approached using the principle of Enten Jizai which means attack and defence are one. The body alignment which evades the attack at the same instant carry an attack to the opponent. The sword/spear principle and empty hand principle are identical.