There is likely no mythological figure in any culture more deeply and timelessly associated with the concept of duality than Persephone, who lives half her life in light and the other half in shadow. The “sisters” in the poem might be interpreted as two literal sisters or two possible life paths that stem from different choices.

In the opening stanza, the recurring idea of duality is presented with “within the house / One sits; the other, without; / Daylong a duet of shade and light” (Lines 1-3). Immediately, the poet uses the image of indoors and outdoors to create a divide between the two girls; furthermore, they are referred to as contrasting “shade and light” (Line 3), again creating a strong sense of duality. However, the poet chooses the word “duet” here (Line 3), which impacts the meaning behind the words. A duet refers to two things that come together in harmony, suggesting that while these two girls have marked differences and polarities, they are not in conflict with one another.

Later, there is duality in the actions and appearances of the two girls. One girl is pale and waif-like, spending her days indoors at her “barren enterprise” (Line 10).