Is the Bansenshukai even worth the paper it is written on???

Is the Bansenshukai even worth the paper it is written on??? Of course, I’m kidding but only partially…

Credibility is defined as the quality of being trusted. In literature, having a credible text means that the information therein is reputable and a trusted source for those looking for information on the subject. In this post, I will go over why the Bansenshukai and possibly other famous ninjutsu texts are not credible, or at least not completely reliable.

When a document is said to be a secret one, passed down only within the clans of the shinobi, or “ninja” for the lay people out there, you would expect it to be accurate. You would expect it to have credibility, right?! After all, from the early 1600’s until the late 1860’s the shinobi families that served the Tokugawa shogun provided a nationwide network of spies, assassins, sharpshooters, etc.

Taken from Wikipedia… “The Bansenshukai was compiled by Fujibayashi Yasutake in 1676, in the early years of the Tokugawa shogunate, to preserve the knowledge that had been developed during the near-constant military conflict from the Ōnin War until the end of the Siege of Osaka almost 150 years later. As well as information on military strategy and weapons, it has sections on the astrological and philosophical beliefs of the times, and along with the Shōninki of 1681 and the Ninpiden of 1560 make up the three major sources of direct information about this shadowy profession.”

So, if this document was meant to preserve secret knowledge for a very specific group of people, the text’s credibility should be considered as of the utmost importance. Should it not?

But, within the Bansenshukai, as with the other documents mentioned, there are several items that are discussed where I am highly skeptical of its validity or accuracy. Of course, most of the document is filled with logical things that make sense, but at times there are things that are just not right.

For example, in the 21st Chapter under the heading “Part 4 of Shinobi Equipment – Fire Devices” there is an entry roughly translated as “the way of the fool’s medicine”. The passage reads as follows…

“Dry the leaves of the marijuana plant and powder them. Three cups of this light brown tea will empty one’s mind and heart, causing one to become a fool.  The leaves of the marijuana plant are best harvested in July.”

There are a couple of major issues with this passage regarding its accuracy.

First is that the leaves of the plant are far less potent than the flower making it necessary to use more of the plant to get the needed effect. To make it tasteless or at least less obvious tasting, you would want to use less of the plant and go with the flower. This is because this is where the psychoactive compound in marijuana (cannabis) known as THC is found in the greatest percentages.

The second problem is that THC does not breakdown in water or even boiling water. Just drinking boiled water with steeped marijuana in it will produce no effect as it will not be absorbed into the body. It will require oil or alcohol to extract the THC from the plant matter and then that extract would have to be added to the tea. I do not think an alcoholic tea would be easily accepted and drank so it would be more practical to make a butter tea. But then again, butter was not a part of the Japanese diet in the Edo Period.

Third, In July there is no psychoactive compounds found in the marijuana plant. At least not enough to have any potency at all. Marijuana in Japan’s climate is harvested in September or October when the THC content is at its highest.

All three points I made can easily be confirmed with a simple Google search.

The passage above, if followed as directed, will give you nothing but a peppergrass tasting tea. The recipient would not be any more foolish than he or she was before they drank it. Just more hydrated.

So, my question to everyone is, are the ninjutsu texts worth studying? 

I even went through different copies of the Bansenshukai to see if this a typo or some kind of mistake. But it was the same in all copies from different time periods.

If something like this is not accurate… what is to say anything else that is written in the text is reliable.

I am not an expert in the big three texts of ninjutsu, but from my experiences looking into them I have found a few different examples just like this one I brought up.

This could be a good reason why the true teachings of ninjutsu have been hidden away inside the art of ninpo taijutsu. That is the vehicle by which students of the Bujinkan Dojo lean ninjutsu, not through the study of texts.

Ninpo Ichizoku!

Sean Askew   BKRBUDO

July 11th, 2022

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