Ninjutsu Inherited (summary)
Lecturer: Jin-ichi Kawakami
Most of conventional researches on Ninjutsu that was systematized during the Edo period and has been inherited since have been conducted on documents such as the books of secrets. However, those written documents were not sufficient for all the knowledge that needed to be conveyed, especially when it included the bodily maneuvers that were difficult to explain in writing. Various oral traditions supplemented stepwise explanation of those specific Ninja method. Therefore, in many cases there are possibilities of intentional editing, alteration and appendix executed in later days. Caution must be taken when examining the words of elders and other record, for putting too much credit on them may result in losing the true nature of the knowledge inherited. The legends on origin of something as well as the knowledge on strange techniques are the issues that especially require that sort of caution, even though investigating the historical and creative background is essential and valuable when understanding Ninjutsu as culture.
Physical techniques are basically handed on within each family. However, not all of them are strictly hereditary, for in some cases pupils were taken in from outside and were allowed their inheritance. Ranking was set for each technique and knowledge, though not universal, based on the mastery and understanding, and as the pupils proceeded from the easy to the difficult, and eventually to the depth of the art, they were allowed to learn a more effective techniques as well as more abstract contents with deep meanings. However, in rare cases, even though they are referred to as "oral" traditions they did keep written documents in order to avoid unwanted omissions and misinformation. There were various religions believed by Ninja, some of which were combined with the Ninjutsu training. They included oral tradition of strange and mysterious techniques, which aimed to gain the virtues of Ninjutsu through enshrining unique deities. Examples of those exotic traditions include the Izuna (fox spirit) method, Mishima dolls, Magatsukami and Anbutsu.
Ninjutsu is a system with broad range that was devised from life technology, which can be categorized as the total survival skill. Investigating its true nature only from the historical aspect is therefore highly difficult. It is necessary to conduct investigation and research from diverse point of view, including physics, chemistry, folklore, physiology and psychology.