In his poem, "Ode to the West Wind," Percy Shelley conveys his message(s) through the use of various figures of speech and literary devices.
In the poem, the speaker discusses both the constructive and destructive powers of the wind. He praises the wind and attempts to communicate with it, imploring the wind to hear him.
He wishes the wind could lift, carry, and push him, as it does dead leaves, clouds, and waves. This suggests he longs for freedom, which is symbolized by the blowing wind. It can also be interpreted as the speaker's desire to die and, in doing so, be free from the hardships of life.
He says, "I fall upon the thorns of life! I bleed!" In these lines, Shelley uses a metaphor to compare the difficulties of life to the thorns of a plant. The speaker feels burdened and oppressed by life.
The word fall and the mental images it evokes contrasts with the sense of freedom suggested by the free-floating, flying wind, which the narrator desperately seeks to experience. He longs for the liberation of being carried by the wind, but is woefully tethered to the earth and life.
The word bleed emphasizes the speaker's suffering. He is not happy in his life which, as suggested by the metaphor of thorns, is painful. He seeks freedom from his pain, and by extension, possibly from life itself.
His desire to be carried away by the wind can either be interpreted as a longing for freedom, or as a desire to die, which is, in a way, the ultimate freedom.