# Niten Ichi-ryū

Traditional Japanese martial art :
| Hyōhō Niten Ichi-ryū ||
| Founder(s) ||
| Miyamoto Musashi (宮本 武蔵 | 1584–1645 |
| Date founded ||
| Early Edo period | Founded between 1604–1640 |
| Current headmaster ||
| There are three successors.*Kajiya Takanori: 12th generation (after Iwami Toshio Genshin) *Musashi Chen (Taiwan): 11th generation *Yoshimoti Kiyoshi: 12th generation (after Kiyonaga Fumiya) ||
Arts taught :
| Japanese name | Description | Niten Ichi-ryu designation |
| Kenjutsu 剣術—odachi, kodachi | Sword art—Long and short sword | Tachi/Kodachi Seiho |
| Kenjutsu—odachi, kodachi | Sword art—Long and short sword used together | Nito Seiho |
| Aikuchi | | Aikuchi roppo |
| Juttejutsu—Jutte | Truncheon art | Jitte to jutsu |
| Bōjutsu棒術—Bō | Staff art | Bo jutsu |
| Jōdō | Staff art | Jo jutsu |
Hyohō Niten Ichi-ryū (兵法 二天 一流), which can be loosely translated as "the school of the strategy of two heavens as one", is a koryū (ancient school), transmitting a style of classical Japanese swordsmanship conceived by Miyamoto Musashi. Hyōhō Niten Ichi-ryū is mainly known for the two-sword—katana and wakizashi—kenjutsu techniques Musashi called Niten Ichi (二天一, "two heavens as one") or Nitō Ichi (二刀一, "two swords as one").

## Origin

Musashi originally studied Enmei Ryū and Tōri Ryū, which were ryūha founded by his grandfather Miyamoto Musashi no Kami Yoshimoto and his father Miyamoto Muninosuke respectively. Musashi eventually focused in the kenjutsu and nitōken and developed his own style.
Around 1640, Musashi intended to pass on his art to three successors from among his thousand students; specifically, to Terao Magonojo, his younger brother Kyumanosuke and to Furuhashi Sozaemon. He considered Magonojo to excel in technique but to lack in reflection, while Furuhashi excelled at reflection but lacked technique. Magonojo received the treatise, the Go Rin no Sho. Hosokawa Mitsuhisa made two copies—one for Furuhashi and one for himself, which he transmitted under the name of Ihon go rin no sho. The best known edition today is this Hosokawa copy. Kyumanosuke was a well known warrior and student of Musashi's at the time. Before becoming leader of the school, he fought in the Shimabara Rebellion in 1638. His service there earned him gold and a robe from the Tokugawa shogunate.
Magonojo died in 1645 and yielded the role of successor to his younger brother Kyumanosuke who had received the Hyoho San-jugo from Musashi. It was Kyumanosuke who transmitted this document to his students with seven added instructions called the Hyoho shiji ni kajo.
Shortly before his death, Musashi also wrote the Dokkodo ("Going My Way"). It seems to be a list of rules that one should try to follow in life steeped in Buddhist precepts.

## Philosophy and Strategy

The Hyōhō Niten Ichi-ryū is more than just a technical school of swordsmanship—it is deeply rooted in Musashi's strategic and philosophical principles, many of which are outlined in The Book of Five Rings (Go Rin no Sho). Musashi emphasized the importance of adaptability, rhythm, and perception in combat, believing that a true martial artist should not be bound by a single weapon or style but should instead be fluid and versatile.
One of the core principles of Niten Ichi-ryū is "ken no sen" (initiative with the sword), which means taking the offensive and controlling the fight from the outset. Musashi believed that passivity in battle leads to failure, and thus his techniques encourage continuous movement and proactive strikes to unbalance opponents. This philosophy is particularly evident in the Niten Ichi two-sword strategy, which allows practitioners to control both distance and tempo by engaging with the katana and wakizashi simultaneously.
Another fundamental concept in Musashi’s strategy is "heiho no michi" (the way of strategy), which extends beyond martial arts and applies to all aspects of life, including leadership, business, and personal growth. He advocated for "seeing things as they truly are", urging practitioners to develop an unbiased perception of reality rather than being distracted by appearances. This concept is reflected in the training methods of Niten Ichi-ryū, where students practice various weapons and scenarios to cultivate mental flexibility and quick decision-making.
Even today, the teachings of Hyōhō Niten Ichi-ryū continue to influence martial artists and strategists worldwide. Its emphasis on adaptability and tactical awareness makes it a martial art not just for combat but for strategic thinking in all walks of life.

## Succession

Succession in the Hyoho Niten Ichi-ryū (the name given by Musashi towards the end of his life) does not follow a hereditary pattern. It is attested to by the bestowing of two artifacts: a scroll on which is written the name of the techniques and the approach to them that must be transmitted if the school is to be perpetuated truly, and a wooden sword that Musashi made himself, with which he trained and used as a walking stick during the last years of his life, today in possession of the city of Usa's Shinto Shrine.
The original title for leaders of Musashi's school were called "Sōke," which translates to leader of the family. The Sōke title was done away with by Imai Masayuki in 2003.
Terao Kyumanosuke (Motomenosuke) had received the complete transmission of the School of Musashi, with certification and Musashi's two swords. He at first refused to teach and sent what he had received to Musashi's adopted son, Iori. Iori refused the succession, since the honor had not been bestowed upon him. With this, Kyumanosuke then agreed to take over as head—both his and Iori's actions were manifestations of their respect for Musashi.
Kyumanosuke would go on to have six sons with five practicing Niten Ichi-ryū. Those sons were Fuji-tsugentaka, Bensuke Nobumori, Goemon Katsuyuki, and Terao Nobumori. It was Nobumori that was the most adept at the art and was handed down possession of the school before Kyumanosuke died in 1688.

### Modern Lineage

In 1908, Aoki Hisakatsu was given the soke title from Santo Kiyotake. He studied under Kiyotake for 21 years. Aoki took training so serious that he would swim in full armor.
In 1920, Aoki moved to Taiwan and began teaching in private schools. He lived and taught there until the end of World War II. He moved back to Japan but left Musashi's scroll and wooden sword handed down for safe keeping due to Japan's ban on combat sports that facilitated “the removal and exclusion from public life of militaristic and ultra nationalistic persons.” Aoki's student returned the relic in 1958.
In 1968, Aoki named Kiyonaga Tadanao and Gosho Motoharu dual soke of the school.

### Dispute

The Gosho-ha Niten Ichi-ryū disputed the lineage claiming that Iwami Toshio Gensho is the sole legal representative of Hyōhō Niten Ichi-ryū until 2007. Miyagawa Yasutaka established a line of Niten Ichi-ryū that continues to practice and thrive in the Kansai region of Japan. Miyagawa Yasutaka and Kiyonaga Tadanao were both students of Aoki Kikuo during the same period. This "Kansai" line, currently under 10th Headmaster Miyagawa Morito, is an alternate but equal lineage to the main line.

### Lineage

The lineage to date is as follows:
* Shinmen Miyamoto Musashi-No-Kami Fujiwara no Genshin 新免宮本武蔵守藤原玄信
* Terao Motome-no-suke Nobuyuki 寺尾求馬助信行
* Terao Goemon Katsuyuki 寺尾郷右衛門勝行
* Yoshida Josetsu Masahiro 吉田如雪正広
* Santo Hikozaemon Kyohide 山東彦左衛門清秀
* Santo Hanbe Kiyoaki 山東半兵衛清明
* Santo Shinjuro Kiyotake 山東新十郎清武
* Aoki Kikuo Hisakatsu 青木規矩男久勝
* Kiyonaga Tadanao Masami / Miyagawa Yasutaka
* Imai Masayuki Nobukatsu / Miyagawa Morito
* Iwami Toshio Gensho/ Kiyonaga Fumiya / Chin Kin (Taiwan)
* Kajiya Takanori (successor of Iwami Toshio Gensho) / Yoshimochi Kiyoshi (successor of Kiyonaga Fumiya) (Current) (Current)
* Ishii Toyozumi (successor of Yoshimochi Kiyoshi)

## Techniques

Today the following sets of techniques and forms are transmitted:
1) Tachi Seiho (太刀勢法) Twelve techniques with long sword:
* 指先 Sassen
* 八相左 Hasso Hidari
* 八相右 Hasso Migi
* 受流左 Uke Nagashi Hidari
* 受流右 Uke Nagashi Migi
* 捩構 Moji Gamae
* 張付 Haritsuke
* 流打 Nagashi Uchi
* 虎振 Tora Buri
* 数喜 Kazuki
* 合先打留 Aisen Uchidome
* 余打 (アマシ打) Amashi Uchi
2) Kodachi Seiho (小太刀勢法) Seven techniques with a short sword:
* 指先 Sassen
* 中段 Chudan
* 受流 Uke Nagashi
* 捩構 Moji Gamae
* 張付 Haritsuke
* 流打 Nagashi Uchi
* 合先 Aisen
3) Nito Seiho (二刀勢法) Five techniques with two swords corresponding to the five forms in the Water Scroll:
* 中段 Chudan
* 上段 Jodan
* 下段 Gedan
* 左脇構 Hidari Waki Gamae
* 右脇構 Migi Waki Gamae
4) Bōjutsu—Twenty techniques with a long staff bō(including techniques Bō Vs Bō and Bō Vs sword).
5) Aikuchi roppo, both.
6) Jitte to jutsu—Five techniques against a sword.