In Japanese folklore, tsukumogami (付喪神 or つくも神, lit. "tool kami") are tools that have acquired a kami or spirit. According to an annotated version of The Tales of Ise titled Ise Monogatari Shō, there is a theory originally from the Onmyōki (陰陽記) that foxes and tanuki, among other beings, that have lived for at least a hundred years and changed forms are considered tsukumogami. In modern times, the term can also be written 九十九神 (literally ninety-nine kami), to emphasize the agedness. According to Komatsu Kazuhiko, the idea of a tsukumogami or a yōkai of tools spread mostly in the Japanese Middle Ages and declined in more recent generations. Komatsu infers that despite the depictions in Bakumatsu period ukiyo-e art leading to a resurfacing of the idea, these were all produced in an era cut off from any actual belief in the idea of tsukumogami. Because the term has been applied to several different concepts in Japanese folklore, there remains some confusion as to what the term actually means. Today, the term is generally understood to be applied to virtually any object "that has reached its 100th birthday and thus become alive and self-aware", though this definition is not without controversy. History and etymology The word つくも髪, which is also pronounced , appeared in a waka poem in the 9th-century The Tales of Ise, section 63. It is a compound of , of unknown meaning, and 髪 'hair'. In the poem it referred to an old woman's white hair, so has been interpreted as meaning "old", often metaphorically represented as ninety-nine years. The element 髪 'hair' is a homophone of 神 'spirit'; both may be pronounced in compound words. Thus the word has come to mean a 99-year spirit. The kanji representation for in this sense dates to a Tenpō period otogizōshi, an emakimono called the Tsukumogami Emaki. According to this emaki, a tool, after the passage of 100 years, would develop a spirit (kami), and with this change would become a . This emaki has a caption stating that the word could also be written with the kanji , meaning 'ninety-nine' (years). Outside of these uses, the word is not attested in the surviving literature of the time, and so the historical usage of the term itself has not been handed down in detail. The concept, however, does appear elsewhere. In collections such as the late Heian period Konjaku Monogatarishū,