This paper is a study of the sentence pattern and usage in Japanese adjective predicative sentences that express Idoukankei. The adjectives that express the meaning of Idoukankei include the original adjective hitosii (“to be equal”) and the transferred adjectives chikai and tooi (“near” and “far,” respectively). These two types of adjectives differ in many ways, such as how they are used in sentence pattern and the characteristics of their usage. The overall results of the analysis are as follows.
(1) Hitosii has two uses: “judgment of similarity based on comparative criteria” and “judgment of sameness.” The main sentence patterns of the former were “N2ha･ga＋N1ni＋A” and “N3ni＋N2ha･ga＋N1ni＋A”; for the latter, they were “N1ha･ga＋A,” “N2ha･ga＋N1to＋A,” and “N2ha･ga＋N1ni＋A.” (2) The main usage of chikai and tooi was: “judgement of movement based on comparison criteria.” The main sentence patterns of this usage were “N2ha･ga＋N1ni＋A,” ‘N2ha･ga＋N1to＋A,” and “N3ni＋N2ha･ga＋N1ni･kara＋A.” (3) The usages “judgment of similarity based on comparative criteria” for hitosii and “judgement of movement based on comparison criteria” for the phrase “chikai, tooi” shared many similar characteristics, including the number of different categories in the sentence, use of postposition, subject of the judgment, and replacement of the noun phrases themselves (or the order). However, there was no single-category sentence in these usages.
(4) The usage “judgment of sameness” for hitosii indicates the comparison of multiple objects. The main sentence patterns were single-category sentences in which hitosii replaced the noun phrase itself and two-category sentences in which the order changed such that the subject was not being judged.
(5) As the main usage of the postposition, ni and kara represented the criteria for judgment and to the object of the judgment.