The ninth center of power is the aura of the body.
The aura consists of an electromagnetic field surrounding the physical self, radiating in all directions.
The strength and extent of the field are determined by the individual.
The kanji represents the acquisition of the secret knowledge.
To become a Ninja, one must accomplish four things: one must be strong; one must know; one must dare; and one must be silent.
It was said of the ancient Ninja that he could become invisible at will.
This may be the myth and legend of a bygone era; it may be that simple tricks and ruses led to this belief; or it may be that the Ninja of old could actually alter the state of his aura and the surrounding atmosphere by physiopsychic means, rendering himself unseeable.
One skilled in this technique would, quite naturally, be reluctant to demonstrate it, and would certainly never reveal his method to the uninitiated.
This art is sometimes known in Kuji Kiri as “the power to cloud men’s minds.”
Remember, the Tao that can be told is not the eternal Tao.
It cannot be explained, but it can be experienced.
This is the goal of meditation.