Updated on 2024/06/17


KARAISL, Antonia
Affiliated organization, Waseda Institute for Advanced Study
Job title
Assistant Professor(non-tenure-track)




  • Faculty of Political Science and Economics   School of Political Science and Economics

Internal Special Research Projects

  • Sangaku versus Euclidean Geometry: A history of tangents or parallel lines?


     View Summary

    Sangaku (算額) present a custom unique to Japan: as votive tablets showcasing mathematical problems, they were dedicated in temples and shrines throughout Japan, starting from the Edo period and well into the twentieth century. The central effort of this research project is devoted to the compilation of a bilingual digital archive of all sangaku (算額) surviving to date in Japan. Doing so, we hope to open up this rich cultural heritage to international scholarship and to put Japan’s idiosyncratic mathematical discourse on the map of the global history of mathematics.The project has commenced in April 2023 and will proceed for a duration of 3 years, in a continued effort to collaborate with researchers of the history of mathematics in Japan, temples, shrines, municipal institutions and other holders of sangaku. Whilst the metadata for each sangaku has already been obtained and converted into digital format, the bulk of the task now is to travel to shrines and temples to take high resolution photographs of the sangaku that still survive.Funding from the Tokutei Kadai Research Base Creation has been used to create the basic predicaments to make this project possible. Half of the funding was used to purchase a high-resolution digital camera and a high-quality lens suitable for taking photographs of sangaku. Since some of the sangaku are suspended in eaves or dark locations, the use of this special equipment has been indispensable for taking photos of a quality high enough to facilitate deep zooming. Since many sangaku are faded or otherwise degraded, this often means surfacing content that would otherwise not be visible to the naked eye.The other half of the grant was spent on travel expenses. Around 950 sangaku survive spread out throughout the country. The compilation of the archive therefore requires a considerable amount of travel to the respective locations. The funding from the Tokutei Kadai grant sponsored travel necessary for documenting ca 120 sangaku. Together with images obtained from other sources, this brings up the count to ca. 200 images, that is approximately 20% of the total amount of images to be made available in the final archive.