"Edge" is one of the last poems that was written by Sylvia Plath. It is considered by some to be simply about death, but others claim that the themes involved are more complex, given that it was one of Plath's last poems before she committed suicide at age thirty. Here are three possible themes of the poem:

Theme #1: The Relief of Death

The relief of death and/or suicide is present through certain diction in the poem. The first five lines of this poem starts with the declaration "The woman is perfected," and Plath later uses phrases that insinuate that death is a restful state of being compared to living. "We've come so far, it is over" emphasizes rest and that the woman in the poem is at peace with her own death. The dead body of the woman also "wears the smile of accomplishment," which further emphasizes this theme.

Theme #2: The End of Necessities in Death

The imagery of dead children in the poem could imply that the woman was their mother or guardian. Each of the children holds an empty "little pitcher of milk." This description suggests that the needs of the children, such as sustenance through the milk that could have been in the pitcher at one point, are ended by the death.

Theme #3: Death Is Bleak and Inevitable

Many of the images in the poem implies that death is bleak and lacks the vibrancy of life through the lack of colors:

• "bare" feet, as opposed to feet with fine sandals or other shoes, could suggest that the life that the woman led was poor or barren, and because of this, death was inevitable for her.
• "white serpents" could be a symbol of the sinister nature of the children's death. This could especially be the case due to the juxtaposition of this description of the children near their white pitchers.
• The "hood of bone" is a detached description of the moon's visage as it hangs over the dead woman and children. By this description and the following line—"She is used to this sort of thing"—one can glean that the personified moon has a "hood of bone" because she has seen many deaths.