MY POINT (BEFORE I LOSE MY MUSICAL TRAIN OF THOUGHT MYSELF) IS THAT
Dogen was a very highly educated, intellectual, "head like a library of old Zen/Buddhist books", surprisingly conservative (as were most Zen teachers, in fact) guy who was highly trained and conversant in the "classics" and was working from them (the Shobogenzo is wall to wall references and quotes from Sutras, old Koans, obscure but important bits of Tendai Buddhist teachings, old poems, Confucian classics, and the like).
There --IS-- a logic to Dogen most of the time, although a Zenny "Anti-logic logic
" ... Dogen-Think-Not Thinking
, a kind of "Alice in Wonderland" logic sometimes. It is more than simple "sound for sound's sake" expression or trying to abandon "intellectual analysis" at every turn. Dogen wanted to be understood on all levels. Thus (as in listening to Jazz), it is --both-- a matter of letting the sound and feeling wash over one, --and-- having some musical understanding of where the musician was "coming from" what he was "trying to do" and how he "got there"
. (In a sense, Jazz was always music by musicians playing for other musicians who were familiar with the chords).
Here are just a few examples of "Dogen-logic", very different from ordinary logic while yet faithful to classic Mahayana perspectives ...
A = Buddha Enlightenment B = Flowers in the sky (a classic Zen reference to delusion)
A is A, B is B ... and A is not B. (Enlightenment is not delusion, an ancient Buddhist idea)
But A is B. A is also C. ... (a variation on the original theme, much as stodgy ol' Nagarjuna might play)
And, in fact, A is so much A that A is not A, and was merely B all along.
We might say that A is just ?. B is merely
And that just makes A into Super-Aness at each turn, B into Be Bee BB "To be or not to be" "Be my love" "B is for Buddha" ... etc. etc.
Smell them luscious Flowers in the Sky! That's purely A through and through, though not.
For that reason, the truth is that Dogen was not trying to defy "intellectual analysis" or "classical Buddhist/Zen philosophy", so much as find his own language and way to express it (in later years, represented by his Eihei Koroku, he actually seems to have abandoned much of the "musical experiment" that was the Shobogenzo, and gone back to being a pretty classical musician playing the "old Zen standards" in the usual way ... though never without his special touch). So, the book I recommended by Taigen Dan Leighton (coupled with a reading of the Lotus Sutra) ... and the Dr. Kim books (though themselves hard going in parts) should not be overlooked by someone really hoping to "Grok" where that Dogen cat was coming from. 8)