For the last couple weeks, I have been trying to get a handle on around thirty archaic Japanese adverbs. Many of them have several meanings, and some of them even have two diametrically opposed meanings. "Tari," for example, can denote a completed action or a continuing action. Of course, that "tari" is not to be confused with the assertive "tari." How do you tell them apart? Simple--look at the word it is connected to. If it's a verb in the renyoukei form, it's the former (in one sense or another). If it's a noun or the rentaikei form of a verb, it's the latter. Just check the chart of thirty adverbs (each itself available in six or so conjugations, which are needed depending on how the adverb itself functions in the sentence). But how do I figure out what sort of verb form it is? Well, depending on which one of the six verb types it is, it will be conjugated differently. (I love that "keru," "to kick," gets a class of its own even though it is indistinguishable to me from kamiichidan verbs.) Don't worry, you get a chart for those too. Oh, and a chart for adjectives. Yes, of course you have to conjugate adjectives, too! What if I can't even figure out if it's a verb or a noun because it's such archaic language? Break out the kogo dictionary, my friend.
How did I get myself into this? Aren't I a sinologist?
Something about it all is perversely appealing to me, I suppose. Like the language, like the country, Japan always seems to make too much sense to my sinified mind. "If you just master this chart and that set of things and memorize this list, it'll all fall into place," it seems to taunt. The Japanese aesthetic may get stereotyped as minimalistic, but this grammar is positively baroque. The amazing thing is, though, it's all there for you. Grammar imparts meaning. I can imagine looking at a classical Japanese text and saying "No, of course the one doing the action is Genji because the verb is in the rentaikei!"
Contrast that with an (admittedly, rather extreme) example from Classical Chinese. In the Lao Tzu text, there's a line that reads:
無名天地之始 (nothing name heaven earth possessive-particle beginning)
We could take the "name" as a verb and read that as "'Nothing' names the beginning of the world." We could also read "nothing" and "name" as being a noun phrase, giving us "Nameless is the beginning of the world." There's no way to tell, and commentators argued about stuff like this in the margins of texts for centuries. For that matter, they still are.
That's why I am (masochistically) enjoyng Classical Japanese so much, why it seems so novel to me. There's clarity, but you're going to need some maps and charts to get to it.
UPDATE: Matt over at No-Sword has answered the riddle of the single shimoichidan verb "keru-- to kick" in an enlightening post here.