To which other art does Ezra Pound compare the art of poetry?
Ezra Pound compared poetry to music throughout his life. He touted his creation of "Imagism". Imagism was a movements, based on Chinese and Japanese poetry, that stressed rhythm, precision, and succinctness. He rejected formal rhyme and meter schemes. He said himself that he tried to "compose in the sequence of the musical phrase, not in the sequence of the metronome." The metaphor of poetry as music is present both in the content and style of his poetry.
His later masterpiece was called the "Cantos", which of course means "songs".