2025 Theses Doctoral

Lu Ban’s Ruler and Shōtoku’s Saw: An Intellectual History of Carpentry in Premodern Japan

Bertozzi, Nicolle Marr

This project examines the knowledge production of carpenters during the Azuchi-Momoyama (1568–1600) and Tokugawa (1600–1868) periods. Drawing from an interdisciplinary range of approaches, including intellectual history, material culture studies, and the history of science and technology, this dissertation contributes to an ongoing reevaluation of the relationship between “practical” and “theoretical” knowledge in premodern East Asia.

Since ancient times, Japan’s temples, shrines, and palaces have served as symbols of authority for the nobility and religious institutions who funded their construction. In spite of this, the carpenters responsible for constructing these important sites appear only briefly in early historical records. However, the social upheaval of the Sengoku (1467–1600) period brought carpenters to the fore. Regional warlords working to accumulate territory and power sought out talented carpenters from among the construction guilds at temples and shrines to employ as strategic advisors to design and build their fortresses and palaces. After the Tokugawa unified the country in 1600, they appointed the families of carpenters who had served them in the preceding decades to hereditary positions in the government. Many of the families maintained these positions for the duration of the Tokugawa period. The first chapter of my dissertation traces this historical transformation in the status of carpenters in order to contextualize the phenomenon that I explore in the remainder of the dissertation.

With the dawn of the Tokugawa period, carpenters throughout Japan began composing and circulating great quantities of writing. These included hidensho, or manuals of secret knowledge; collections of personal notes and miscellanea; and booklets of model designs and technical drawings. The second chapter of my dissertation focuses on the question of why carpenters, who transmitted their knowledge and expertise through an apprenticeship system utilizing observation and bodily practice, turned to the written word at this time. This chapter argues that carpenters used the written word as a means of consolidating, managing, and organizing information, which they did for a variety of purposes, whether to seek legitimacy, transmit knowledge to the next generation of carpenters, or to create a personalized reference source through which to organize one’s thoughts on the significance of the trade.

The dissertation’s third chapter examines the role that textual transmission played in the spread of the belief that Shōtoku Taishi (574–622), a semi-legendary prince of Japan’s Asuka period (538–710), was the patron deity of carpenters. This chapter considers how carpenters used the prince’s longstanding status as a kind of “boundary object,” which allowed them to render him legible across disparate religious contexts while maintaining his core identity as a visionary who introduced knowledge and technology from the Asian continent to Japan. It ultimately argues that, as the patron deity of carpenters in the Tokugawa period, Shōtoku allowed these carpenters to incorporate continental bodies of knowledge surrounding measuring, mathematics, and the cosmological significance of architectural ratios into their own thinking.

Building on chapter three, the fourth and final chapter of the dissertation argues that carpentry texts on the measuring techniques that Shōtoku was credited with introducing to Japan must be situated within the larger East Asian intellectual tradition exploring measuring as an inherently meaningful act. This chapter reveals that carpenters were, like mathematicians and music theorists, engaged in the intellectual project of using scales of measurement to make sense of the phenomenological world’s position within a larger cosmological system.