Bokusho Volume 23 Fragments

Bokuzeisho Volume 23 Fragment — A Rare Medieval Divination Manuscript Preserved at Kanazawa Bunko

Hidden within the vast manuscript collection of Kanagawa Prefectural Kanazawa Bunko lies a quiet but extraordinary survivor of medieval scholarship: the Bokuzeisho Volume 23 Fragment (卜筮書巻第廿三断簡). Though only a portion of the original twenty-third scroll remains, this Important Cultural Property opens a remarkable window onto the intellectual culture of medieval Japan, where Buddhist monks did not merely chant sutras but also studied Chinese classics, history, poetry, and the ancient arts of divination.

Owned by Shomyo-ji Temple in Yokohama and preserved at the adjacent Kanazawa Bunko museum, the fragment is a piece of the broader manuscript universe that the Kanazawa Hojo family — a powerful warrior lineage of the Kamakura period — assembled at their family temple and library. Few visitors expect a quiet seaside neighborhood of modern Yokohama to hold one of Japan's most remarkable medieval archives, yet that is precisely what awaits those who travel just a short ride from central Tokyo.

What is the Bokuzeisho?

The term "Bokuzei" (卜筮) refers to two of the oldest forms of divination in the East Asian tradition. The character "boku" (卜) originally pictures the cracks that appear when tortoise shells or animal bones are heated for oracular reading — a practice already in use in ancient China more than three thousand years ago. The character "zei" (筮) refers to divination using yarrow stalks, the technique most closely associated with the Yijing (Book of Changes). Together, "bokuzei" came to mean the broad art of foretelling the future or judging the auspicious or inauspicious nature of an event through ritual procedure.

A "Bokuzeisho" (卜筮書), then, is a manual or compilation of divination knowledge, drawing on the long Chinese tradition of the Yijing and related fortune-telling texts. Such manuscripts were highly valued in medieval Japan, where the determination of auspicious days, directions, and undertakings was deeply woven into both court ritual and everyday life. The surviving fragment from volume 23 hints at a once substantial work, suggesting that the original text was an extensive treatise of considerable scholarly weight.

The designation "kan dai nijūsan dankan" (巻第廿三断簡) — "Fragment of Volume Twenty-Three" — tells us that the surviving piece is only a portion of the twenty-third scroll of the original work. The word "dankan" (断簡), literally meaning "broken slip," is a term used in Japanese bibliography for incomplete manuscript fragments. Yet even fragments of this age and provenance are treasures: each surviving sheet of paper preserves brushstrokes, layout, and textual readings that cannot be found anywhere else.

The Setting: Shomyo-ji and Kanazawa Bunko

To understand the fragment, one must first understand its home. Shomyo-ji (称名寺) is a Shingon-Ritsu sect temple founded in the mid-13th century by Hojo Sanetoki (1224–1276), a leading figure of the Kamakura shogunate and the founder of the Kanazawa Hojo lineage. Sanetoki was both a powerful warrior-administrator and an exceptional scholar; he gathered books on politics, history, literature, and Buddhism, eventually establishing a private library beside his residence that would come to be known as the Kanazawa Bunko (金沢文庫). Successive generations of his descendants — Akitoki and Sadaaki in particular — continued to expand both temple and library, transforming Shomyo-ji into one of the leading centers of learning in eastern Japan, sometimes called the "Kanazawa Academy."

The temple itself is a quietly beautiful place. A red gate leads through a cherry-lined path to the imposing Niomon (Deva Gate), beyond which spreads a pure-land style garden centered on the Ajigaike pond. Curved and straight bridges connect a central island and lead toward the Main Hall (Kondo), all carefully restored in the late 1980s based on a 14th-century painted plan of the temple grounds — itself an Important Cultural Property.

The neighboring Kanagawa Prefectural Kanazawa Bunko, the modern successor to the medieval library, holds the temple's manuscripts, paintings, sculptures, and ritual implements. The institution has been steadily organizing, deciphering, and publishing these materials for nearly a century, and the Bokuzeisho fragment is one of the many precious items entrusted to its care.

Why Was It Designated an Important Cultural Property?

The Bokuzeisho Volume 23 Fragment is designated as a national Important Cultural Property (重要文化財) under the ownership of Shomyo-ji, recognized separately from the broader collection of "Shomyo-ji Shogyo and Kanazawa Bunko Monjo" that was elevated to National Treasure status in 2016. Several overlapping reasons justify its protected status.

Rarity of the text

Bokuzeisho-type manuscripts are exceedingly rare in Japan, and complete versions of such large-scale divination compendia have generally been lost. A fragment from a scroll numbered as high as the twenty-third suggests an originally substantial work, and even a single surviving sheet offers irreplaceable evidence of how Chinese divination knowledge circulated in medieval Japanese monastic libraries.

Manuscript provenance

The fragment is part of the celebrated Kanazawa Bunko corpus, transmitted in a single line through the Kanazawa Hojo family and Shomyo-ji from the late Kamakura period to the present. The continuity of this transmission gives the fragment exceptional documentary credibility.

Insight into medieval learning

The text exemplifies the wide intellectual reach of medieval Japanese monks. Far from being concerned only with doctrinal Buddhist works, the learned monks of Shomyo-ji collected and studied Chinese classics, historical records, literary anthologies, and texts on divination, calendrical science, and astrology. The Bokuzeisho fragment is concrete evidence of this scholarly cosmopolitanism.

Highlights and What Makes the Fragment Captivating

A whisper from a vanished library

Standing before the Bokuzeisho fragment is a deeply contemplative experience. The aged washi paper, the careful brushwork, and the elegant arrangement of classical Chinese characters carry the silent voice of an anonymous scribe — perhaps a learned monk at Shomyo-ji, perhaps an earlier copyist whose work survived through generations of careful preservation. Manuscripts of this kind are sometimes described as "time capsules," sealed away when the temple's fortunes declined in the late Muromachi period and only fully rediscovered in the 20th century.

Divination as cultural bridge

The text reminds visitors that medieval Japanese intellectuals were deeply engaged with Chinese learning. Divination, far from being a purely superstitious practice, was studied as a serious philosophical and cosmological discipline rooted in classics such as the Yijing. The fragment is a tangible thread linking the temple library of medieval Yokohama to the ancient scholarly traditions of continental East Asia.

The atmosphere of Kanazawa Bunko

Even when the fragment itself is not on view, simply walking through the galleries of the Kanagawa Prefectural Kanazawa Bunko offers a rare immersion in the world of medieval Japanese manuscripts. The museum's curators rotate exhibitions several times a year, drawing on the temple's vast holdings — National Treasures, Important Cultural Properties, and many remarkable items still under study.

How to Visit and What to See Nearby

Both Shomyo-ji and Kanagawa Prefectural Kanazawa Bunko are located in Yokohama's Kanazawa Ward, easily accessible from central Tokyo by train. The two institutions are connected by a short tunnel through the temple's wooded hillside, an atmospheric passage that itself dates back to the medieval period.

Whether or not the Bokuzeisho fragment is on display during your visit, the experience is rewarding. Shomyo-ji's pure-land garden is one of the most beautiful of its kind in the Kanto region, and the surrounding "Shomyo-ji Citizens' Forest" offers gentle walking paths up to a hilltop pavilion with views toward the bay.

• Shomyo-ji Temple — the historic temple complex itself, with its red gate, Niomon, pure-land garden, and Kondo housing the Important Cultural Property image of Maitreya (Miroku Bosatsu).
• Kanagawa Prefectural Kanazawa Bunko — the museum holding most of Shomyo-ji's documents and treasures, including National Treasure portraits of four Kanazawa Hojo lords and rotating exhibitions from the temple's manuscript collection.
• Kanazawa Hakkei — the eight scenic views of Kanazawa, celebrated since the Edo period; a pleasant short walk from the temple.
• Sea Paradise — a family-friendly aquarium and amusement complex on Hakkeijima island, easily combined with a cultural visit.
• Nojima Park — a coastal park with views of Tokyo Bay, a short distance from the temple.