Mononoke

Mononoke (物の怪) are vengeful spirits (onryō), dead spirits (shiryō), live spirits (ikiryō), or spirits in Japanese classical literature and folk religion that were said to do things like possess individuals and make them suffer, cause disease, or even cause death. It is also a word sometimes used to refer to yōkai or henge ("changed beings").

Mononoke can be often seen in literature of the Heian period. As a famous example, in the 9th volume of the Genji Monogatari, "Aoi", is the ikiryō of Lady Rokujo, who possessed Aoi no Ue. Other than that, there are also statements about mononoke in publications like Ōkagami and Masukagami.

In those times, when medical knowledge has not been fully developed, people like monks and shugensha would perform incantations and prayers against diseases caused by mononoke, and by temporarily moving the mononoke into a different person called the "yorimashi" (usually servants, apprentices, etc.) they would perform exorcism on the mononoke to heal the illness. Statements on this practice can be found in detail in works like the The Pillow Book and The Diary of Lady Murasaki. Also, according to the Shoku Nihon Kōki, it told of once when a monk chanted a sutra to 60 people within the imperial residence.

Japanese "mononoke" come from China's 物怪, and there are statements on them in ancient Chinese literature like Records of the Grand Historian and 原鬼, there are statements on this 物怪. In the latter one, there is the statement, "those with neither voice nor shape are 鬼神 (fiendish gods). Those who cannot have shape or voice, and also cannot be without shape or voice, are 物怪," and thus the 物怪 of China at that time were considered a type of yōkai that cannot be seen or heard, and were thought to be natural phenomena that people did not understand with the knowledge of those times.

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