Nathaniel's poem in "The Sandman," originally written in German by E. T. A. Hoffmann, is the symbol of his madness.

The story tells of a young man who began to feel haunted by a man who had scared him as a child and possibly killed his father. As an adult, Nathaniel thinks he sees this man again.

Though he tries to seek help from his childhood friend and girlfriend, they dismiss his fears and tell him that he is imagining the return of Coppelius. For a long time Nathaniel remains at home, attempting to recover from his fright.

However, during this time he begins writing stories. Unlike the creative stories he wrote as a child, these are dark and sinister. Nathaniel is isolated in his fears and consumed by these dark images which he insists on putting to paper.

Eventually this writing culminates in a poem.

The poem is significant in the story because it is the climax of Nathaniel's madness. He writes it without even realizing what he is writing, and only afterwards realizes how dark it really is. However, he insists on reading it to Clara, who is horrified.

She eventually speaks sense to Nathaniel, and it seems like all is well. He returns to school.

Although it seems like the poem was the end of his madness, he quickly falls back into madness when the Coppelius look-alike returns and sells him an eyeglass with which he begins spying on Olympia.

The glass leads him back toward madness, until he has a breakdown upon realizing that she is not real.

He has returned to Clara and all seems to be well again. However, when he pulls out the glass, madness returns again in force.

The poem had talked about Clara's eyes being taken and turned into fire which burned Nathaniel's heart. When he looks at her through the class he sees this fire and believes that his poem is coming true.

We see, at the end of the story, that Nathaniel was never able to shake his fears and spent much of his life living in the madness which was symbolized by the poem. Although no one had taken Clara's eyes, he was convinced that they had and that she was not a real person.

Ultimately, Nathaniel's madness drives him to jump off the tower and die, making the ending of his poem come true as he finally stares into the eyes of death.