In studying sword we learn to control the kensen, the line that the kirisaki, the tip of the sword, draws in each cut. Eventually we are able to draw that line with our minds eye alone. This ability is one of the secrets of aikido practice. It enables us see the invisible form within each technique and to send out energy precisely to the correct place in our partners body. This ability takes many years to realize; without sword training, the student is much less likely to discover it.Cutting with the Japanese sword is an expansive motion in which the tip of the sword must be unified with ones center. The basic diagonal cut, called kesa giri, may be equated with ikkyo in barehanded aikido training. If one truly masters this one cut, he or she has already realized shin shin toitsu or body-mind unification. Within kesa giri is the secret of natural spiral movement. The sword falls by its weight alone and the weight of the body comes to ride on top of its free fall. The turning of the hips and the subtle connection between your own center and the tip of the sword create effortless power and speed. Just as in aikido, this basic way of cutting with the sword is dependent on a continual expansion of our feeling; in fact, that is the life of the movement itself.
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