BOOK REVIEW: The Book of Ninja [The Bansenshukai] Trans. by Anthony Cummins and Yoshie Minima

The Book of Ninja: The Bansenshukai - Japan's Premier Ninja ManualThe Book of Ninja: The Bansenshukai – Japan’s Premier Ninja Manual by Antony Cummins

My rating: 4 of 5 stars

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The Bansenshukai is a 17th century manual of ninja tradecraft and fieldcraft compiled by Fujibayashi Sabuji. If you’re doing related research or are a geek about historic warriors and / or spies, you’ll likely find this book intriguing–and parts of it even fascinating. However, it’s important to note that this translation’s title The Book of Ninja may conjure up expectations of stories of derring-do and assassinations set in medieval Japan. This isn’t that book. This book contains an extensive discussion of morals, guidance as to how commanders should employ ninja, how to don a disguise and impersonate your way into enemy territory, technical discussion of how to infiltrate long-obsolete fortifications, insight into how to pick medieval Japanese locks, and instructions for how to make torches and rope ladders. This book won’t teach you how to be a ninja. (a.) I suspect no book could do that, b.) This one holds back a lot of secrets, and c.) Most of the information is obsolete from a practical stand point. (However, it’s likely to have many ideas of a strategic or philosophic nature that one might find thought-provoking.)

Why is this book important and interesting (though–as I’ve suggested–some of its content seems patently boring)? We live in an era of information overload, and it’s difficult to fathom how little is truly known about the ninja of medieval Japan. We live during a time in which even the most secretive agencies document everything always (even if they sometimes manage to shred or burn that information.) In their heyday, the ninja weren’t big on writing down true and interesting information for fear it would fall into the wrong hands. Lack of documentation and false documentation were key elements of security. There are only a few manuals like this one in existence, and the Bansenshukai is considered by many to be chief among them by virtue of being the most extensive. (FYI- The other well-known manuals are the Shoninki and the Ninpiden, both of which also have English language translations available. Beyond these manuals, there are some surviving familial scrolls.) It should be noted that these manuals were written after the warring states period (though before the Meiji Restoration) when there was a fear that this information might be lost precisely because it was historically conveyed via word of mouth. And, it should be noted, throughout the work there are frequent statements to the effect of “there is an oral transmission”—meaning that key parts haven’t been written down and are only to be taught in person by hands-on instruction.

The Bansenshukai is organized into 22 volumes. The first volume is background and introductory information. The second and third volumes are more philosophical, dealing with achieving the “correct mind,” the former dealing with morality and the latter offering perspective on life and death.

The fourth through seventh volumes are designed to educate military commanders about how they might get the best use of ninja.

The next group of volumes (8 – 10) cover Yo-nin, which is the act of infiltrating enemy territory in the open through use of disguise and deception. The Japanese term yo is the same as the Chinese term yang, or sunny side—as opposed to yin (in in Japanese) which means the shady side. So these volumes offer advice for operating out in the open—in the light of day, so to speak. The previous volumes are contrasted with the next set of volumes (11-15), the In-Nin, which deals with covertly breaking into enemy houses and castles. Together the Yo-nin and In-nin chapters are likely to be the most interesting to the general reader–excepting the last of these (vol. 15, which deals with lock picking.) While I said that this book isn’t full of stories of legendary exploits, I don’t mean to suggest Fujibayashi didn’t use vignettes to reinforce his points (there are plenty of them)—just that these stories aren’t told to entertain but to educate.

The next two volumes are entitled Tenji I and Tenji II, and they discuss what the author considered the opportunities bestowed by heaven. The first of these chapters is mostly Chinese astrological hokum in painful detail. The second is a primitive primer on meteorology—which I suspect is a mix of good and bad advice based on the science of that time and place. (These people were exceptionally observant but the product of superstitious times, and so one can imagine fact and fiction being muddled together.) At any rate, I found the second chapter to have some quite interesting information of which I’d like to know more about the veracity.

The final set of volumes are on ninja tools (i.e. ninki.) These include chapters on climbing tools like rope ladders, water crossing devices like inflatable seats, breaking and entering tools, and many recipes for incendiary and explosive materials. Like the chapter on locks and lock picking, these chapters will mostly be of value to individuals with a heavy interest in the history of technology—with a particular focus on Japan and / or East Asia. In many ways the ninja were by necessity technologically advanced by the standards of that time in Japan’s history (keeping in mind that because of literally centuries of war, Japan wasn’t at the cutting edge of a spectrum of technology in the 17th century as they are today—though they made swords that at least rivaled if not surpassed those anywhere else in the world, but swords were on the way out or passé by that time in many places.)

There’s an additional text on strategy that forms an appendix to The Bansenshukai. To the front, there’s an explanation of Japanese locks of the time, written by a historian of such minutiae. There’s also front matter by the translator, providing valuable background material. Each chapter is heavily endnoted. These endnotes are generally explanatory in nature. While the text is quite readable given its era, there’s much that requires further explanation. Sometimes the notes elaborate on a statement in the text and sometimes they suggest that an explanation is unknown—either way that information can be quite beneficial. The graphics are simple drawings (I believe they come from the original text), and in some cases they wouldn’t be useful without the explanation of the text.

One will note a heavy Chinese influence in The Bansenshukai. There are frequent references to Sun Tzu and many of the vignettes use to illustrate points involve tales from China—though there are also many that feature Japanese warriors as well—e.g. Kusunoki Masashige, a samurai famous as a paragon of loyalty but who was also known for his use of ninjutsu and unconventional tactics, features prominently throughout the work—though it’s unknown how many of these tales are fact and how many legend.

If you’re still curious about the contents of this book after hearing what it is and isn’t, I’d highly recommend it. There’s a lot of thought-provoking information in the book, and if you’re doing research on the subject this book is essential reading. I should also point out that while I’ve suggested that much of the information is obsolete in the modern era, it’s not all so. There are some interesting perspectives on strategy, tactics, philosophy, and ethics in this book. [Plus, if you want to be the office ninja, it’s a must-read along with Machiavelli’s The Prince.]

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READING REPORT: March 6, 2015

This will be a brief reading report. I finished just one book this week, as well as purchasing only one book.



The book that I finished was a translation of the Bansenshukai, which is a 17th century ninja manual written / compiled by Fujibayashi Sabuji. The Japanese title means “10,000 Rivers Flow into the Sea,” but this English translation by Anthony Cummins and Yoshie Minami was re-titled The Book of Ninja. I ran into a hard-copy of this book in a Kuala Lumpur bookshop, but ended up purchasing the much cheaper Kindle e-book. I read about half of the book months ago, and only got around to finishing it this week.


There’s much that will forever remain unknown about the ninja and their medieval practices. The Bansenshukai is one of three well-known manuals that survived into the modern era–along with the Ninpiden and the Shoninki (each of which also has at least one English translation.) It should be noted that these manuals were generally written after the heyday of ninja activity, and still the most common sentence in this book is some variant of the phrase “There is an oral teaching”, meaning that important details have been kept out to preserve secrecy. This is a book of tradecraft, don’t expect thrilling exploits of the ninja, much of the book deals with minutiae about medieval lock picking and recipes for incendiaries. While the English translation title may beckon images of black-clad ninja stealthily rolling over the top of a wall to dispatch an unsuspecting sentry via death from above, the bulk the material is much more mundane. This is a great book for people who geek out on Japan’s Warring States period or who are doing research regarding this topic (I fit in both categories as my novel takes place in part in medieval Japan.)



The book I bought is Sam Harris’s Free WillHarris is a neuroscientist who studies issues that have historically been considered the domain of religion and spirituality, but he does so from a scientific point of view. What one believes about free will is likely to form the bedrock of one’s personal philosophy of life, so this is a very important topic, and I have high hopes for learning something new from this book.


The only other book that took a significant portion of my time is one that I introduced earlier:

WhyDoPeopleGetIll_Leader&CorfieldLeader and Corfield explored the immune system and issues related specifically to cancer in the chapters that I read this week. It was a pleasant turn for the book into a more scientific and less psychobabbly landscape. I continue to be intrigued by this book and it’s title question.


That’s it for now. I’ll be posting reviews for The Book of Ninja as well as last week’s Antifragile in the upcoming week.