When a Shadow is not a Shadow — Miyamoto Musashi’s Yin and Yang

Miyamoto Musashi, arguably Japan’s most famous warrior, needs no introduction. Martial arts enthusiasts from all over the world have heard of his life and feats and many have read Gorin no Sho, a.k.a. The Book of Five Rings, which has been translated into several foreign languages. Musashi however wrote a few more treatises that people outside Japan may be unaware of. The following is a list of Musashi’s writings:

  • Heidōkyō 『兵道鏡』 written in 1605.

  • Heihō Kakitsuke 『兵法書付』 achieved in 1638. This text is little-known, even in Japan.

  • Heihō Sanjūgo Kajō 『兵法三十五箇条』 written in 1641.

  • Gohō no Kamae no Shidai 『五方の構の次第』, an addenda to the Heihō Sanjūgo Kajō detailing five fighting stances, mainly taken from the Heihō Kakitsuke.

  • Gohō no Tachi no Michi 『五方之太刀道』 probably written around 1642-43.

  • Gorin no Sho 『五輪書』 Musashi’s “best seller”, brushed in 1645.

  • Dokkōdō 『独行道』 completed in 1645, a few days before his death.

Musashi explains many aspects of dueling with swords and martial strategy in his different treatises, but in this article I would like to focus on the “yin-yang” concept that Musashi describes in Gorin no Sho and Heihō Sanjūgo Kajō. In Heihō Sanjūgo kajō, Musashi introduces two complementary articles about an elusive concept of “shadow”: “On Pressuring the Shadow” and “On Moving the Shadow”. Those two articles are in fact quite difficult to render in English. First of all, the Chinese character used to write “shadow” is different in each case. In the first article, Musashi uses 陰, which can be read as “kage” but also “in”, i.e. yin or the passive principle of Chinese cosmogony. In the second one, Musashi chooses 影 to write “kage”, also pronounced “yō”, or yang, the active principle. Secondly, several sentences of those articles are rather ambiguous and can thus be interpreted in different ways. Generally, translators who work on these sections do not attempt to render the yin-yang concept and make do with translating everything as “shadow”.

陰のかげをおさゆると云事、敵の身の内を見るに、心の余りたる処もあり、不足の処も在り。我太刀も、心の余る処へ、気を付る 様にして、たらぬ所のかげに其儘つけば、敵拍子まがひて勝能物也。されども、我心を残し、打処を不レ忘所、肝要なり。工夫あ るべし。

On Pressuring the Shadow (yin)

Pressuring the shadow (yin) means when you examine the posture of your enemy, you will see places where his mind overflows and places where it is deficient. You first feign to pressure with your sword a place where his mind overflows, then suddenly pressure a place where it is deficient (1): your enemy’s rhythm will be disrupted and you will be victorious. It is however important that you keep your mind clear and you do not forget the place you should strike (2). This requires practice.

影は陽のかげ也。敵太刀をひかへ、身を出して構時、心は敵の太刀をおさへ、身を空にして、敵の出たる処を、太刀にうてば、か ならず敵の身動出なり。動出れば勝事やすし、昔はなき事也。今は居付心を嫌て、出たる所を打也、能々工夫有べし。

On Moving the Shadow (yang)

Yang is the shadow of yin. The enemy is on guard, his body to the fore and his sword to the rear. You pressure the enemy’s sword with your mind, making your body empty (3). If you strike where your enemy steps in, he will have to change his posture (4). If he moves, you will be easily victorious. This kind of technique wasn’t used in the past (5). Nowadays, people do not like immobility; it is thus best to strike what comes at you (6). This requires a lot of practice.

Points of discussion:

(1) You first feign to pressure with your sword a place where his mind overflows, then suddenly pressure a place where it is deficient.

In fact, the word to word translation of this sentence is “You first feign to pressure with your sword a place where his mind overflows, then suddenly pressure the shadow of a place where it is deficient”. The problem here is that Musashi writes shadow in hiragana (かげ) so it is up to interpretation on whether he is talking about yin, yang or just shadow. Fortunately, when it comes to Heihō sanjūgo kajō, there is an additional source on which we can rely upon: Enmei Suisaiden Bibōfu『円明水哉伝備忘譜』. This treatise was completed in 1711 by Suisaiken Souda Yasushige, a master of the Enmei school of swordsmanship, which was founded by one of Musashi’s adopted sons. Enmei Suisaiden Bibōfu contains many explanations about the philosophy of the Enmei-ryū and also an extensive commentary of Musashi’s Heihō sanjūgo kajō. Regarding “On Pressuring the Shadow”, Suisaiken explains that “Yin is the shadow. It is something that does not appear”, so yin refers to the places where the opponent’s mind is deficient. He adds that by pressuring the enemy where he is strong, he will end up in a state where his mind is “divided”. This in turn will exacerbate the difference between his strong and weak places. The enemy will then focus on the pressure exerted on his strong place and won’t be able to react when the pressure suddenly shifts to a weaker place. At this point, like Musashi states, the “enemy’s rhythm will be disrupted and you will be victorious”.

(2) It is however important that you keep your mind clear and you do not forget the place you should strike.

Continuing on what has been said in point (1), if the enemy’s focus is on the pressure exerted on his strong place, he will most likely lose the fight. However, this is conversely true for the other swordsman. To put it in simpler terms, what Musashi says here is that you shouldn’t be engrossed on pressuring the enemy’s strong place to the point of missing the occasion to shift to the weaker place.

(3) You pressure the enemy’s sword with your mind, making your body empty.

“Making your body empty” is the literal translation of 身を空にして. It is however possible to translate this sentence as “without showing your intentions”. This is outside the scope of this article, but this way of interpreting 身を空にして seems more accurate, based on another duality used by Musashi throughout the Heihō sanjūgo kajō: the distinction between the will, strong but easily read by the opponent, and the heart or mind, unfathomable but potentially subject to changes. This duality is also discussed in the Enmei Suisaiden Bibōfu.

(4) If you strike where your enemy steps in, he will have to change his posture. This sentence is ambiguous. The literal translation is above, but it can also be interpreted as “strike where your enemy’s body standsout, he thus will have to move (to dodge)”. Suisaiken uses the same formulation without explaining it.

(5) This kind of technique wasn’t used in the past.

This sentence is a bit obscure. Suisaiken explains in his commentary that it should be understood as “this technique does not exist in the other schools”, but does not give any other information.

(6) Nowadays, people do not like immobility, it is thus best to strike what comes at you. This formulation is also rather abstruse. It is neither explained in Enmei Suisaiden Bibōfu, nor re-used by Musashi in the Gorin no Sho. Itis probably linked to the point discussed in (4), but this is only a supposition.

Yin & Yang and why it matters

It is important to remind here that in Musashi’s days, many schools were using the words yin and yang to explain their kamae (sword stances). Thus a “yang stance” was generally accepted as a posture where the sword is in front of the body and a “yin stance” where the tip of the sword was behind the body. This meant that the sword was considered as the yang principle of the duel and the body as its yin.


Nonetheless, in Heihō Sanjūgo Kajō, when Musashi “pressures the yin”, he applies pressure with his sword onto a place where his enemy’s mind overflows (most likely the enemy’s weapon); and when he “moves the yang” he forces his opponent (whose sword is at the rear) to change his posture (i.e. he moves his enemy’s body). This way of interpreting those two articles would thus reveal that Musashi thinks in opposition to his contemporaries. For him, a “yang stance” would be a posture where the sword is at the rear and a “yin stance” a kamae where the sword is in front of the swordsman, thus making the sword the yin and the body the yang element of a sword fight. To corroborate this idea, it is interesting to note that although Heihō Sanjūgo Kajō is a treatise on sword fighting, Musashi talks mainly about the body, often about the mind, but seldom about the sword. The body is his principal topic.

Moreover, in Heidōkyō (Musashi’s very first attempt at writing down his fighting theories), we can find an article called “In no Kurai” (yin) that describes a fighting stance with the swords in front, followed by a second article “Yō no Kurai” (yang) which explains a wakigamae stance with the swords pointing to the rear.

That is interesting because Musashi finally changed his mind in Gorin no Sho! In his later treatise, he indeed “pressures the yang” and “moves the yin”. Thus, the contents of the article “On Moving the Shadow (yin)” in Gorin no Sho resembles that of “On Moving the Shadow (yang)” of Heihō Sanjūgo Kajō, and accordingly the contents of the article “On Pressuring the Shadow (yang)” in Gorin no Sho shares some ideas with “On Moving the Shadow (yin)” of Heihō Sanjūgo Kajō.

一 陰をうごかすと云事。
かげをうごかすと云ハ、 敵の心のミへわかぬ時の事也。 大分の兵法にしても、 何とも敵の位の見わけざる時ハ、 我方より強くし かくる様にみせて、 敵の手だてを見るもの也。手だてを見てハ、 各別の利にて勝事、やすき所也。 又、一分の兵法にしても、 敵うしろに太刀を搆、脇に搆たる様なるときハ、 ふつとうたんとすれバ、 敵思ふ心を太刀にあらはすもの也。 あらはれしるゝにお ゐてハ、其まゝ利をうけて、 たしかにかちをしるべきもの也。 油断すれバ、拍子ぬくるもの也。 能々吟味有べし。

On Moving the Shadow (yin)

Moving the shadow is something you do when you cannot read your opponent’s intention. In large scale strategy, if you cannot discern the enemy’s intentions, feign a strong offensive: the enemy will most likely reveal his hand. When he does, you can easily achieve victory by using the appropriate tactic. Likewise, in a sword fight, when the enemy is on guard with his sword to the rear or at his side, if you suddenly feign to strike, the enemy’s intentions will appear in his sword. When you catch his intention, you should immediately seize the advantage and be able to asses how to achieve victory. If you do not pay enough attention, you will miss the opportunity. This needs to be studied thoroughly.

一 影をおさゆると云事。
かげを押ると云ハ、敵のかたより、 しかくる心の見ヘたるときの事也。 大分の兵法にしてハ、 敵のわ ざをせんとする所を、おさゆると云て、 我方より其利を押る所を、敵に強く見すれば、 強きにおされて、敵の心かはる事也。 我 も心をちがへて、空なる心より、 先をしかけて勝所也。 一分の兵法にしても、 敵のおこる強き氣ざしを、 利の拍子を以てやめさ せ、 やみたる拍子に、我勝利をうけて、 先をしかくるもの也。能々工夫有べし。

On Pressuring the Shadow (yang)

Pressuring the shadow is something you do when you see that the enemy is willing to attack. In large scale strategy, when the enemy is about to execute his tactic, you must quell it: if you present yourself as very powerful, the enemy will feel the pressure and will change his mind. Change your own tactic accordingly, and without showing your intentions, take the initiative to achieve victory. In a sword fight, when the enemy’s intentions become visible, break them by using an advantageous rhythm. The enemy will freeze for an instant. Seize this opportunity to achieve victory and take the initiative. This requires a lot of practice.

Thus, in Gorin no Sho, the yin configuration describes the enemy in a traditional yin posture, with the tip of the sword behind his body. Musashi suddenly feigns to strike, forcing the enemy to move and therefore revealing his intentions through his sword, the yang principle. Musashi then pressures the intentions in the second article to achieve victory. We do not know why Musashi changed his views on yin and yang. One may think that he might have wanted to “harmonize” with the theories of his days. I personally find it unlikely, considering how he tries to firmly distance himself from the teachings of other schools in the “Scroll of Wind”. Maybe he thought it would be easier to explain it in this manner, although it has always seemed to me that the contents of Heihō Sanjūgo Kajō is way more practical and easy to grasp than that of Gorin no Sho...

To conclude, analyzing this yin and yang concept is a good way to demonstrate the limits of many translations of Miyamoto Musashi’s works. Another case to consider would be the duality “i no kokoro” and “shin no kokoro” that Musashi use throughout his treatises and which is very rarely rendered in foreign languages. This will be perhaps the subject of a future article.


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