Written Japanese, fundamentally standardized by the eighth century, had undergone sporadic and incremental change prior to the Meiji period, evolving into a collection of documentary, epistolary, and narrative styles that were firmly bound in the classical language. The spoken language, on the other hand, which had developed considerably over the centuries, reflected the multiple dialects and complex hierarchies of contemporary Japan. The disparity between writing and speech caused great concern for Meiji leaders, both because learning the written language took a great deal of time and effort and because it was a barrier to mass literacy. Although Tokugawa literature contained examples of colloquial dialogue, writers and scholars sought a narrative style that was closer to speech yet flexible enough to be used in formal contexts.
Futabatei Shimei is generally credited with the first successful use of a vernacular style in his novel Ukigumo (1887; tr. The Drifting Clouds, 1967). However, Futabatei gives credit for his model of colloquial narrative to rakugo storyteller San’yutei Encho, whose collaboration with Takusari Koki (inventor of sokki, Japanese shorthand) allowed rakugo stories to be published in newspapers. Other writers quickly joined the so-called genbun itchi (unification of writing and speech) movement, to which there was opposition through the 1910s. Publishing houses adopted the new style in their children’s literary journals, such as Akai Tori, and other massmarketed publications, which led to its widespread adoption. The use of classical written styles continued among some authors, however, for several decades.
With that background, Matt focuses on “the mass of past and/or perfective verb endings”:
That particular part of Japanese reached its peak of complexity during Early Middle Japanese; it’s been a downhill slope of simplification ever since, and today we’re basically down to the –ta ending. But because Early Middle Japanese also served as the model for Classical Japanese, as the centuries rolled on the literary community were expected to master and preserve fine distinctions of a sort that their native language clear-felled and paved over increasingly far back in the mists of history.
He quotes “a marvelous rant on this topic by Ochiai Naofumi 落合直文, from an essay published in 1890 called ‘Shōrai no kokugo’ 将来の国語 (‘The national language/Japanese of the future’),” which I highly recommend. Peevery is ubiquitous and eternal!