Sounds as well as thoughts

Percy Bysshe Shelley finds a relation between the order of words into sense and the order of sounds into a sort of music. By ?a sort of music? I only mean that ?harmonious recurrence of sound,? as Shelley puts it. ?A perception of the order of (that relation),? he writes, ?has always been found connected with a perception of the order of the relation of thoughts.? This seems to hold that there is something essential about poetic language. This seems to allow for cries of ?simplification? but I do not understand him to mean that prehistoric man had a poet comparable to Milton. He does not. I see the beginning of an argument both for and against poems such as odes to nightingales. To what extent is lyrical beauty enough to classify as poetry? Must it not also have sense, logic, even complicated thought? I cannot quite discern which type of poetry Shelley would feel is highest. A better question might be: which of his poems did he like best? To a Skylark or England in 1819?