Contrast

Throughout the poem, the power and potential of the natural elements contrast with the immovable, helpless mood of the speaker.

quote
the wind tugs energetically at the sail

However, the speaker seems unable to harness this potential into something positive, stating that my heart is dumb. The word choice of dumb has several connotations in this instance: the speaker feels empty as he also implies that he knows that there is no logic to his pursuit. What is clear is that, while the world whirls around him, the speaker stays still.

The speaker also contrasts with the girl of the red-gold hair: she is described as the bringer of music (with implied vibrancy) while he remains indifferent and bereft.