 Among other twentieth century Japanese philosophers, Yuasa Yasuo, known for his theory of the body, often refers to the doctrines and practices of Shingon Buddhism, and has writen entire chapters on Kūkai in Shintairon: Tōyōteki shinshin ron to gendai and The Body: Towards an Eastern Mind-Body Theory. Comparative philosopher of religion, Izutsu Toshihiko, as well, in Ishiki to honshitsu and other works, has found Kūkai’s ideas – especially his cosmological-linguistic theory – inspiring enough to incorporate into his own theory of essence as part of his attempt to build a synthetic “Oriental philosophy” (tōyō tetsugaku). Philosopher of Buddhist thought, Tamaki Kōshirō discusses the significance of Kūkai’s philosophy within the history of Japanese Buddhism in his Nihon bukkyō shisō ron. And philosopher of religion and religious studies scholar Nakazawa Shin’ichi, like Ueda, focuses on Kūkai’s mandalic philosophy in his book, Seppen kyokusenron. He reads Kūkai’s works on Shingon as involving a hydrodynamic mode of thinking that in its flexibility deals with the non-Euclidean currents of nature with its forces of reality, undulating in ripples and forming vortexes. He views the Shingon mandala as approximating, with its circles and lines, what is expressed in today’s fractal geometry, whereby the infinitesimally microcosmic part endlessly and indefinitely iterates the patterns of the whole of nature in its innumerable vortexes and curves.