Reassembling the Written, Rewriting the Mind: The Emergence of “Thoughtography” (Nensha) in Meiji Psychology

Abstract

In late 1910, Tokyo Imperial University psychologist Fukurai Tomokichi announced his discovery that thoughts could be inscribed directly onto photosensitized surfaces—a power he dubbed nensha 念写, subsequently rendered into English as “thoughtography.” The ensuing debates over such powers structured a landmark demarcation struggle over the boundaries of science and pseudoscience in modern Japan. This article takes a new and yet unexplored approach to such demarcation struggles by first asking: what were nensha as visual and material artifacts? In response, I argue that Fukurai’s experiments belonged to a wider history of inscription. In Meiji Japan, brush, pen, woodblock, movable type, telegraphy, phonography, and photography destabilized inherited assumptions about writing, authorship, intention, and mind. Experimental psychologists such as Motora Yūjirō and Fukurai reassembled these media into apparatuses for studying reading, writing, attention, will, and communication. Reframed in this context, I propose that nensha represented Meiji psychology’s response to a crisis in written communication: an attempt to recover the presence of mind amid proliferating mechanical inscriptions. On this basis, I then reframe late-Meiji demarcation as a contest among rival hermeneutics of visible traces. To decide whether thoughtography was science was to decide what inscriptions could count as evidence, who or what could write, and how the human mind might be made legible.