Paper short abstract:

I discuss the historical changes in the distribution of -tu and -nu, using the Corpus of Historical Japanese. In the Nara Period, -tu followed volitional verbs while -nu followed non-volitional verbs, and -tu rarely co-occurred with -keri. In the Heian Period, there existed unpredicted patterns.

Paper long abstract:

From the 7th century to now, Japanese people have written various materials, some of which reflected the contemporary spoken language. In pre-modern times, the most part of Japanese people were monolingual, and the Japanese language changed chiefly by internal factors. In order to examine the historical changes over such a long span, it is effective to utilize the Corpus of Historical Japanese (CHJ). I discuss the historical changes in distribution patterns of the perfective markers -tu and -nu from the Nara to Heian period, using the CHJ.

In the 8th century Japanese poetry collection Man'yoshu, -tu and -nu followed verbs in strictly regular ways: -tu followed volitional verbs while -nu followed verbs concerned with non-volitional or natural change. In addition, -nu often co-occurred with the past tense marker -keri and formed -nikeri while -tu rarely co-occurred with -keri. The speakers in the Nara period would intuitively grasp these differences of -tu and -nu; therefore exceptions hardly occurred.

In the Genji Monogatari of the early 11th century, the usage of -tu and -nu began to be confused. We can find the unpredicted patterns of -nu with volitional verbs and -tu with non-volitional verbs, and there existed not a few examples of -tu with -keri, which formed -tekeri.

This confusion further progressed in the Konjaku Monogatari-shu of the mid-12th century. Moreover, the previously stative marker -tari was reanalyzed as a perfective marker and took the place of both -tu and -nu. The form of -tari eventually changed to -ta, which is still used now. Concatenations such as -teiru and -teari emerged as complex aspectual elements at this age. I examined these phenomena quantitatively and qualitatively with the CHJ.