In modern Japanese, it is difficult for a non-volitional verb to take the imperative form; instead, it is better to accompany non-volitional verbs with a benefactive auxiliary verb. However, in old Japanese, it is common for non-volitional verbs to take the imperative form. Similar relations are satisfied by the imperative form of adjectives, the negative auxiliary verb Zari, and the attitudinal expression On-Ari, which is used in middle Japanese. In this paper, I estimate that that it was during the early Edo period that the use of imperative forms with non-volitional verbs diminished. This diminution was caused by a preference for benefactive auxiliary verbs, a preference that was, in turn, caused by a change in the directive expressions system
