out fatigue, breath control, and various ways of walking to avoid sound
and, thus, detection. They also had to be skilled at climbing, employing
various tools to assist them, such as rope ladders and metal claws that at-
tached to the hands. Working often at night, they trained to increase their
ability to see in the dark and hear especially well.
Ninjutsu scholars note forms of chanting, magic spells, incantations,
and mudras (hand gestures) in order to focus one’s mental power and re-
ceive divine protection. These techniques presumably derived from similar
esoteric Buddhist practices of yamabushi (mountain warriors), shugendô
practitioners whose purpose was to attain Buddhahood through such asce-
tic discipline. Though secondary sources often stress these magical aspects
of ninjutsu, major texts are silent regarding them.
Yet clearly, severe spiritual training was necessary to accomplish dif-
ficult missions. Thus, the first two sections of Bansen shûkaistress spiri-
tual or mental preparation. “A correct mind [seishin] is the source of all
things and all actions. Now, since ninjutsu involves using ingenuity and
stratagems to climb over fences and walls, or to use [various ninja tools]
to break in, it is quite like the techniques of thieves. If someone not rever-
ing the Way of Heaven should acquire [ninjutsu] skills and carry out evil
acts, then my writing this book would be tantamount to revealing the tech-
niques of robbery. Thus I place greatest importance on a correct mind”
(Bansen shûkai1982, 438).
Yasutake devotes two sections to developing a correct mind. Rather
than providing prescriptions for spiritual training such as techniques of
meditation or the use of mudras, he instead quotes from classical Chinese
texts espousing that the ninja practice Confucian virtues of loyalty, benev-
olence, justice, and truth. Yasutake considers the most essential ingredient
of the correct mind for a ninja to be the ability to rise above concerns for
life and death, which he notes is as hard for a man to comprehend as it is
for a bird to speak. He explains the workings of the universe in terms of
the interaction of yin and yang and the five elements, in order for students
to understand that life and death are intimately related and thus death is
natural: “Life is man’s yang, and death is his yin,” as he puts it (Bansen
shûkai 1982, 459).
The practice of ninjutsu has been revived since World War II and
taught openly in several places in Japan. It has also been exported abroad,
with the result that there are centers of training in so-called ninjutsu in
many places throughout the world. Several years ago, on a Japanese What’s
My Line,a young American stumped the panel, who could not discern that
his occupation was ninja. As the martial arts have become international-
ized, cross-fertilization has taken place, with the result that schools teach-
ing ninjutsu often incorporate standard techniques from karate, kung fu,360 Ninjutsu