Jundo Cohen Koans, the way they were originally developed (before Dahui made them an object for concentration on a phrase during Zazen in the Rinzai way) and the way Dogen and others use them in our Soto Way, are basically teaching tools. There is a logic to them, but just not our normal “common sense” logic (which is the often incomplete). Most of the Koans “make sense” in Buddhist and Mahayana terms, and contain our perspectives. Koans can be explained, and were not developed merely as absurd and totally senseless stories.
The idea that Koans are meant to be totally meaningless, absurd and just monkey wrenches to the brain is ridiculous. For example, in ordinary logic a chair is not a mountain, and there is birth and death. In Zen, a chair is not a mountain yet it is, as are you too, and there is no birth or death while birth is thoroughly birth and death is just death. Koans just help us understand such points. No, they are not merely to be understood with the brain intellectually, but one might say that they need to be understood with a freshly open and unbounded brain and felt deep in the bones. They are often meant to be fun too (They usually contain humor. Part of the difficulty we have with them is that the old Chinese jokes, puns, sayings and poetic references are hard to translate now … but people got the jokes and cultural references back then. Chinese “Chan/Zen speak” of certain historical periods (in trying to convey both time and the timeless) developed its own styles, inner puns and jokes, standard allusions (like “upright and inclined” or “host and guest” were code words for the “absolute and relative”) and symbols (e.g., white cranes in the snow). Although also beyond all thought of “time or place”, the great distance of time and cultures, and the resulting gap in shared cultural references and language may actually make some phrases more “mystical and mysterious” than they were at the time to readers who recognized the references, sayings and the shared code. Often Zen phrases seem “cryptic”, mysterious and profound simply because many old Zen stories were written in 1000 year old “slang”, citing forgotten Chinese legends or poetic references, all of which was sometimes then poorly translated or remembered over the years! It is as if I were to create a Koan now using such ‘Americanism’ terms as “bling-bling”, “shake your booty”, “here goes nothing”, “Thomas the Tank Engine” (Britishism) and “Casey at the bat” and expect folks 1000 years from now in Lithuania to “get the reference”. They might take “Bling Bling” to be a mysterious Mantra thought to have fantastic magical powers.🙂 ). Gassho, Jundo