In the student's efforts to compose his own essay, he may wish to note that there have been two popular interpretations of "La Belle Dame sans Merci." One is that the lady is a person who is the object of the knight's love, and the other is that the "lady/dame" is the metaphysical concept of beauty. In either case, however, the knight is helpless in his faithfulness to his love, for the more one embraces feelings of love and beauty, the more desolate and painful mundane life becomes.
Keats's narrative poem, which is written in ballad form, is arranged as a dialogue as the speaker is unidentified in the first twelve lines. When the question "O what can ail thee?" is asked, the reader's knowledge of chivalric legend and lore points to love since a lily pallor and faded rose point cannot relate to the other two allegiances of a knight, his allegiance to God and to his lord.
However, the knight does not describe a woman; it is a faery that he loves: "She took me to her elfin grot," and held him "in thrall." This mythical spell placed on the heroic figure of a knight has caused the hillside to be cold and the sedge withered. Only when the spell is broken can the land be fertile.
Because this "Belle Dame sans Merci" is a faery, many interpret her as the concept of beauty or art. And, thus, is the plight of the artist who must live in the world of art or suffer the disappointment and desolation of the mundane. Certainly, this idea can be related to many musicians who, while delighted as they play their instruments, are often disillusioned or unhappy when not engaged in their music, seeking something to cure their "blues," and it is this despondence and unhealthy condition that causes their deaths--the "sans merci."