Writing is thinking
It's not the only form of thinking (I'm not some kind of scriptosupremacist), but writing is—in one sense—giving some kind of external, potentially durable form to ideas. Maybe those ideas are externalized really explicitly, like a proof. Maybe they're best conveyed in impressionistic sketches, where the purest form of the idea lives only in the rhythm or the flavor of the words as they linger in your mouth. Maybe the writing is inscrutable because the incomprehensibility itself is the idea. Maybe the idea is "how do i get cowboy paint off a dog ."
Lovely that they're all out there in the world, ripe for a different brain (or maybe the same one!) to think them all over again.