Kagakushū


The Kagakushū, alternatively read as Gegakushū, was a 1444 Japanese dictionary of Chinese characters arranged into semantic headings. The title alludes to Confucius' self-description in the Lunyu: 下学而上達 "My studies lie low, and my penetration rises high."
The Kagakushū's colophon is dated 1444 CE, but does not name the dictionary's editor except for obscurely mentioning Tōroku Hanō. Scholars presume this was a Muromachi Period Buddhist priest because Tōroku is a variant name for Tōzan, which is the location of Kennin-ji, the head temple of the Sōtō school of Zen.
The Kagakushū was one of the first Japanese dictionaries designed for common people rather than intelligentsia. In the lexicographical evolution of Japanese dictionaries, Nakao explains how
eference books took a significant further step towards Japanese, and the dictionaries, which had been almost exclusively employed by scholars, priests, literati, and the learned minority of the country, consequently reached a wider audience and began to be used as practical guides to reading and writing. Moreover, the developing technology of printing enabled the literate public to obtain handy and practical dictionaries quite cheaply. Kagakushu, produced in two volumes and edited by a monk in Kyoto, was a sort of Japanese language dictionary with encyclopedic information. It served as a textbook on Chinese characters and was reissued many times, each time with further additions.

This anonymous Japanese dictionary, in two fascicles, defines some 3000 words. Head entries in the Jikyōshū give the kanji, Japanese readings in katakana to the right, definition, usage notes, and occasionally etymology. Collation for the entries involves 18 semantic headings, as shown below.
HeadingRōmajiKanjiSubject
1Tenchi天地nature
2Jisetsu時節seasons
3Jingi神祇Shintō deities
4Jinrin人倫human relations
5Kan'i官位offices and ranks
6Jinmei人名names of people
7Kaoku家屋buildings
8Kikei気形creatures
9Shitai支体anatomy
10Taigei態芸art and form
11Kenpu絹布cloth
12Inshoku飲食foods and drinks
13Kizai器材utensils
14Sōmoku草木plants
15Saishiki彩色colors
16Sūryō数量weights and measures
17Genji言辞miscellaneous words
18Jōji畳字synonym compounds

Compared with the semantic categorizations in earlier Japanese dictionaries such as the Wamyō Ruijushō or Iroha Jiruishō, these simplified 18 in the Kagakushū are easier to understand.
Many Kagakushū editions have an appendix entitled Tenkaku-shōji that lists pairs like ya "smelt; cast" and chi "govern; regulate".
The origins of the Kagakushū, like the Setsuyōshū, are associated with an early type of Japanese textbook used in Buddhist Terakoya private schools, the ōraimono. According to Don Bailey:
The Kagakushū, although only sparsely annotated, was in fact intended to serve as a small encyclopedia and textbook as well as a dictionary; the compiler, apparently realizing that many of the ōrai then in use were too detailed, cumbersome, and tome-like, condensed and abstracted from these texts in order to produce a reference tool containing minimally essential information and Chinese characters. That he succeeded is attested by the fact that over thirty copies of the Kagakushū have survived from the Muromachi period alone.