On the Japanese Verb Kikoyu: Semantic Expansion of Comprehension Usage

Verbs of involuntary hearing that also express auditory inference (comprehension based on hearing) are known to exist in multiple languages. However, the verb 𝘬𝘪𝘬𝘰𝘺𝘶 (聞こゆ) in Old Japanese, which expressed auditory inference, uniquely evolved to express general comprehension in the early modern period. Regarding comprehension usages of this verb, 𝘛𝘩𝘦 𝘎𝘳𝘦𝘢𝘵 𝘋𝘪𝘤𝘵𝘪𝘰𝘯𝘢𝘳𝘺 𝘰𝘧 𝘈𝘳𝘤𝘩𝘢𝘪𝘤 𝘑𝘢𝘱𝘢𝘯𝘦𝘴𝘦 (『角川古語大辞典』) presents three specific ways of usage: auditory comprehension (auditory inference), comprehension concerning speech, and general understanding.
This study aims to identify the emergence periods of these usages and to elucidate the cognitive mechanism underlying this semantic change. The analysis is based on the 𝘊𝘰𝘳𝘱𝘶𝘴 𝘰𝘧 𝘏𝘪𝘴𝘵𝘰𝘳𝘪𝘤𝘢𝘭 𝘑𝘢𝘱𝘢𝘯𝘦𝘴𝘦, covering the period from the 8th to the 20th century.
The findings indicate that, firstly, during the 8th and 9th century, the usage of involuntary hearing is only observed, whereas the usage of auditory inference emerges in the 10th and 11th century. Secondly, the usage of comprehension concerning speech is observable from the 10th century, but it becomes more frequent around the 17th century. Thirdly, the usage of general understanding (comprehension unrelated to hearing) is attested from the 18th century. Additionally, pragmatic usage that does not specify the object of comprehension appears in the 19th century.
The semantic shift from auditory inference to deeper comprehension can be explained through a synecdochic relationship: the generalization of meaning might have been progressively executed by the conceptualizer, beginning with the meaning of auditory inference. This repetitive generalization results in the conventionalization of new synecdochic meanings and enhances the degree of the lexical item, allowing for pragmatic usage without specifying the object of comprehension. For example, “Hahā kikoeta” (𝘈𝘬𝘦𝘨𝘢𝘳𝘢𝘴𝘶 𝘯𝘰𝘤𝘩𝘪-𝘯𝘰 𝘮𝘢𝘴𝘢𝘺𝘶𝘮𝘦『明烏後の真夢』 in 1824) translates to “Ah, I see.”