Indeed, if a chief question does remain: how is the power to think possible? - The power to think right and left, before and without, with and above experience? then it does not take a deduction to prove the genealogical priority of language.
But I liked Yeats! That wild Irishman. I really loved his love of language, his flow. His chaotic ideas seemed to me just the right thing for a poet. Passion! He was always on the right side. He may be wrongheaded, but his heart was always on the right side. He wrote beautiful poetry.