How did Alexander Pope argue that poetic sound should match poetic sense?

In his didactic poem An Essay on Criticism, Alexander Pope argued that for poetry to be effective, it is not enough to simply avoid harshness; rather, the sound of the verse must serve as an "Echo to the sense".12

Pope advocated for a form of onomatopoeia in prosody, where the movement of sound and metre directly represents the actions or subjects being described. He illustrated this principle through specific examples:12

• Gentle movement: When describing soft subjects like a breeze or a smooth stream, the verse uses fluid, gentle language.12
• Rough movement: When describing powerful or difficult actions, such as a torrent or a character struggling to throw a heavy rock, the verse becomes "hoarse" and "rough," with words that move slowly to mimic the physical effort.12
• Swift movement: Conversely, when describing rapid action, the rhythm of the line quickens to mirror the speed of the subject.12

By aligning the acoustic qualities of the language with the meaning of the text, Pope believed poets could achieve a more profound and expressive impact.12