To best describe the theory of this ‘style’ of Karatedo, it is divided into two sections, the mental and the physical as each has its own prerequisites, some very specific Shotokai, others more general to Budo.

The mental requirements are more applicable to all Budo, but are practiced by students of Shotokai. The concept Mushin No Shin (mind of no mind) is best explained as no conscious thought, reaction becoming reflex. It is necessary to clear the mind of distracting thoughts, including those of fear to enable instinctive reaction and ryochi, intuitive wisdom to take control of the situation.  Zenshin (whole mindedness) prior to any engagement is vital, through tsushin, during the engagement, merging with zanshin, constant alertness following engagement. Tsuki no kokoro - mind like the moon, being able to see all things equally and be totally aware of any changes is part of this state of mind. Irimi, entering the mind of the opponent so as to anticipate his action gives control over the situation. Mittsu no sen, the three methods of timing are the only possibilities when facing an opponent: go no sen (block then counter-strike), sen no sen (taking the initiative as the opponent moves, but before he completes his attack) and sen sen no sen or ki no sen (sensing the moment the opponent‘s mind has decided to attack then initiating a pre-emptive strike). Focus or Kime merges the mental with the physical, the silent Kiai also directing the Ki energy from its power base in the hara or centre to the contact point with the opponent.

Along with Kime and Kiai, Kokoro the mind, comes Waza, the techniques. The vital requirements of shotokai are relaxation of the muscles (apart from a contraction of the muscles in, for example, the ipponken, first finger single knuckle) combined with flexibility, heaviness and feeling of centre, this is the ‘power’ behind shotokai techniques. Along with this is the concentration, the kime, speed and total commitment to the technique, penetrating as if the opponent was not there, with ki flowing. Maai, distance is used to control the opponent, dictating the techniques available to him at the given range.

In tsuki, punches, the fist should be as an iron ball with the arm a piece of elastic joined to the hips. The fist is then thrown from the hip through the target. There must be no tension in the bicep or other arm muscles down the forearm when striking and ki must be concentrated at the point of impact. The same principle applies to geri, kicks with again the hips becoming the dynamic behind the kick and the appropriate part of the foot, koshi, sokuto, haisoku the concentration point. With striking techniques such as tettsui, uraken, gedan barai etc the wrist joint must be supple and flexible, enabling the fist to mirror the action of a hammer onto its target and making penetration of vital points accessible with particular parts of the fist, finger joints etc. With open hand techniques such as teisho, again the flexibility of the wrist makes the whipping action of the palm heel far more devastating than a rigid strike. This total flexibility adds considerable ‘power’ to shuto and haito techniques. It is vital that Ki power is not dispersed before reaching the target, so the shortest route to the target is taken, by the attacking hand, foot or other weapon. This also gives extra speed and ensures no effort is wasted. There are very few techniques where this is not the case, eg mawashi geri and mawashi tsuki, roundhouse kick and punch, but these were only added to karate in the latter part of the last century and do not appear in any authentic kata.

At all times the centre of gravity must be low and the Ki power controlled in the tanden, lower abdomen. Controlled breathing practice aids in the cultivation of Ki, breathing in through the nose, taking the breath up over the head, down the spine, under the body and coiling it in the hara, then the out breath coming up the body from the depths of the lungs, up the chest and exhaled through the mouth with the tip of the tongue placed on the upper palate. Exhalation needs to be from the very bottom of the lungs and with time this breathing will show very little rise and fall of the chest, giving less opportunity for the opponent to see initial movement before attack. The ability to draw in breath at speed and exhale with control adds to the heaviness and focus of Ki.

To ensure total focus of Ki, when moving forwards or to the rear the step is straight, (not bringing the foot in and out in a crescent shape like other styles, eg shotokan) and low stance is adopted to give a heavy, centred, balanced base. The dynamics of body movement are using the hips and Ki power in the hara to move the body, rather than leading with the head and shoulders, keeping a low centre of gravity whilst moving, whether slowly or at speed during a technique. The knees must never be ‘locked’, but must always be flexed, slightly bent to facilitate rapid movement. Balance and harmony in both the physical body and the mental state are required to give total kime.

During ‘blocking, punching, striking’ techniques hikite, the withdrawing hand is employed for several purposes. Hikite gives extra power to the technique through the hip movement and can be used to disrupt the balance of the opponent by drawing him onto the technique or propelling him in another direction. The yin / yang, positive / negative of this push / pull movement makes the outward strike more effective and balances the body.

The devastating effects caused by striking the vital points of the body are used, concentrating the Ki to these points can damage the opponent in a possibly fatal way. There is no random attack to the trunk, head, legs etc, instead the strike is aimed at points on the conception and governor meridians, stomach, gall bladder, liver, heart, lung, large intestine, small intestine, pericardium, kidney, spleen and three heater meridians to effect damage, disrupt ki flow and control the opponent. For this purpose the single knuckle and other small striking surfaces are used for maximum penetration. Of the numerous points available, a selection of ‘dangerous’ points are used which are most effective in the control or defeat of an opponent. These include points on both the anterior and posterior of the body and what are known as the seven restricted locations, a strike to which could be lethal.