In Poetry I have a few axioms, and you will see how far I am from their centre. I think Poetry should surprise by a fine excess and not by singularity — it should strike the reader as a wording of his own highest thoughts, and appear almost a remembrance — Its touches of Beauty should never be halfway thereby making the reader breathless instead of content: the rise, the progress, the setting of imagery should like the Sun come natural to him — shine over him and set soberly although in magnificence leaving him in the luxury of twilight — but it is easier to think what Poetry should be than to write it — and this leads me on to another axiom. That if Poetry comes not as naturally as the leaves to a tree it had better not come at all.

Letter to John Taylor (February 27, 1818). - Letters (1817-1820)