From the Translator's Introduction

The Book of Five Rings and The Book of Family Traditions on the Art of War are two of the most important texts on conflict and strategy emerging from the Japanese warrior culture. Originally written not only for men-at-arms, they are explicitly intended to symbolize processes of struggle and mastery in all concerns and walks of life.

The Book of Five Rings was written in 1643 by Miyamoto Musashi, undefeated dueler, masterless samurai, and independent teacher. The Book of Family Traditions on the Art of War was written in 1632 by Yagyu Munenori, victorious warrior, mentor of the Shogun, and head of the Secret Service.

Both authors were professional men-at-arms born into a long tradition of martial culture that had ultimately come to dominate the entire body of Japanese polity and society. Their writings are relevant not only to members of the ruling military caste, but also to leaders in other professions, as well as people in search of individual mastery in whatever their chosen path.

The Book of Five Rings and The Book of Family Traditions on the Art of War are both written in Japanese, rather than the literary Chinese customary in elite bureaucratic, religious, and intellectual circles in Japan at that time. The Japanese in which they are written, furthermore, is relatively uncomplicated and quite free of the subtle complexities of classical high court Japanese. Although the crudity of Musashi's syntax and morphology make for clumsy reading, nevertheless the basic simplicity and deliberate clarity of both works make them accessible to a wide and varied audience.

The rise and empowerment of the samurai class in Japan may be seen in the two terms used to refer to its members, samurai and bushi. The word samurai comes from the Japanese verb saburau, which means "to serve as an attendant." The word bushi is Sino-Japanese and means "armed gentry." The word samurai was used by other social classes, while the warriors referred to themselves by the more dignified term bushi.

The original samurai were attendants of nobles. In time their functions expanded to the administration, policing, and defense of the vast estates of the nobles, who were mostly absentee landlords. Eventually the samurai demanded and won a greater share of the wealth and political power that the nobles had called their own. Ultimately the military paragovernment of the Shoguns, known as the Bakufu, or Tent Government, overshadowed the imperial organization and dominated the whole country.

Musashi and Yagyu lived in the founding era of the third Tent Government, which lasted from the beginning of the seventeenth century through the middle of the nineteenth century. While inheriting the martial traditions of its predecessors, this third Tent Government differed notably in certain respects.

The first Tent Government was established in eastern Japan near the end of the twelfth century and lasted for nearly one hundred and fifty years. The warriors of this time were descendants of noble houses, many of whom had honed their martial skills for generations in warfare against the Ainu people in eastern Japan. As the Tent Government was seated in Kamakura, a small town near modern Tokyo, this period of Japanese history is commonly called the Kamakura era.

The second Tent Government supplanted the First in 1338. The warrior class had expanded and become more differentiated by this time, with lesser and thinner genealogical ties to the ancient aristocracy. The Shoguns of this period established their Tent Government in Kyoto, the old imperial capital, and tried to establish high culture among the new samurai elite. This period of Japanese history is commonly called the Ashikaga era, after the surname of the Shoguns, or the Muromachi era, after the name of the outlying district of Kyoto in which the Tent Government was located.

To understand Japanese history and culture, it is essential to realize that no government ever united the whole country until the Meiji Restoration of 1868. The imperial government had always ruled the whole land in theory, but never in fact. The imperial house had never really been more than a center of powerful factions, competing with other powerful factions. Even when everyone recognized the ritual and political status of the emperor in theory, direct imperial rule only reached a portion of the land.

As this is true of the imperial house, so it is also true of the military governments. The reign of the Shoguns was always complicated and mitigated by the very nature of the overall Japanese power structure. The rule of the Kamakura Tent Government was not absolute, that of the Muromachi Tent Government even less. Separatism, rivalry, and civil warfare marked the fifteenth and sixteenth centuries.

By this time, known as the era of the Warring States, the way of war was open to anyone who could obtain arms by any means. Lower-class samurai rose up to overthrow the upper-class samurai, and Japan was plunged into chaos. It was not until the latter part of the sixteenth century that a series of hegemons emerged with strategy and power sufficient to move dramatically toward unification. The third Tent Government was built on the achievements of those hegemons.

Within the context of traditional Japanese society, the founder of the third Shogunate was an upstart and a usurper. Aware of this, he set out to establish a most elaborate system of checks and controls to ensure the impossibility of such an event ever occurring again. Moving his capital again to eastern Japan, away from the heartland of the ancient aristocracy and imperial regime, the new Shogun disarmed the peasants and disenfranchised the samurai class, removing all warriors from the land and settling them in castle towns. This period of Japanese history is commonly known as the Tokugawa era, after the surname of the Shoguns, or the Edo period, after the name of the new capital city, now called Tokyo.

Tokugawa Japan was divided into more than two hundred baronies, which were classified according to their relationship to the Tokugawa clan. The barons were controlled by a number of methods, including regulation of marriage and successorship, movement of territories, and an elaborate hostage system. The baronies were obliged to minimize their contingents of warriors, resulting in a large number of unemployed samurai known as ronin, or wanderers.

Many of the disenfranchised samurai became schoolteachers, physicians, or priests. Some continued to practice martial traditions, and to teach them to others. Some became hooligans and criminals, eventually to constitute one of the most serious social problems of the later Tokugawa period. Certain differences, both technical and philosophical, between The Book of Five Rings and The Book of Family Traditions on the Art of War stem from the fact that Miyamoto Musashi was a masterless samurai pursuing a career as a dueler and an independent teacher of martial arts, while Yagyu Munenori was a distinguished war veteran and a servant of the central military government.

The Book of Five Rings
More properly titled in English The Book of Five Spheres, Miyamoto Musashi's work is devoted to the art of war as a purely pragmatic enterprise. Musashi decries empty showmanship and commercialization in martial arts, focusing attention on the psychology and physics of lethal assault and decisive victory as the essence of warfare. His scientifically aggressive, thoroughly ruthless approach to military science, while not universal among Japanese martialists, represents a highly concentrated characterization of one particular type of samurai warrior.

Although a vast body of legend grew up around his dramatic exploits, little is known for certain about the life of Miyamoto Musashi. What he says of himself in The Book of Five Rings is the primary source of historical information. He killed a man for the first time when he was thirteen years old, for the last time when he was twenty-nine. At some point he apparently gave up using a real sword but continued to inflict mortal wounds on his adversaries until the end of his fighting career.

The last three decades of Musashi's life were spent refining and teaching his military science. It is said that he never combed his hair, never took a bath, never married, never made a home, and never fathered children. Although he also took up cultural arts, as indeed he recommends to everyone, Musashi himself basically pursued an ascetic warrior's path to the end.

Born into strife, raised in mortal combat, ultimately witness to a transition to peacetime polity on a scale unprecedented in the history of his nation, Miyamoto Musashi abandoned an ordinary life to exemplify and hand on two essential elements of ancient martial and strategic traditions.

The first of these basic principles is keeping inwardly calm and clear even in the midst of violent chaos; the second is not forgetting about the possibility of disorder in times of order. As a warrior of two very different worlds, a world of war and a world of peace, Musashi was obliged to practice both of these fundamental aspects of the warrior's way in a most highly intensified manner, lending to his work a keenness and a ferocity that can hardly be surpassed.