Poetry is the form that was here before prose, before story as we now understand it, because human beings needed to mark what exceeded ordinary language before they needed to explain it — grief, ecstasy, the particular light at a particular hour that arrived and was gone. It works by compression and resonance rather than elaboration, which is why a well-made poem can outlast centuries without instruction: it does not tell you what to feel but arranges the conditions in which feeling becomes precise. To practice poetry is to practice the discipline of saying only what cannot be left out.
Each step builds on the last.