[Machine Translation] The Edo period (1603-1868) was a time of peace and prosperity. With the rapid development of the commodity economy and the publishing media, yokai became "characterized. Suddenly, these creatures that had frightened humans became tools for entertainment. There were "yokai illustrated books" depicting popular yokai, manuals for "yokai magic tricks" to make yokai appear at will, and "yokai toys" such as toy pictures and dolls. This groundbreaking theory of yokai discusses the shift in Japanese attitudes toward yokai, from fear to entertainment, as well as the shift in the Japanese worldview.