Robert Frost worked on the poem “Design” for several years before first publishing it in 1922, and he tweaked it afterwards, ultimately including it in his 1936 collection A Further Range. The poem is a deceptively simple 14-line sonnet that takes up a huge question as its theme: if there is intelligent design in the universe, then why does that design include dark and dangerous forces? Frost uses the example of a spider perched on a flower, having caught a moth. Yet the implication is much deeper than that, obliquely raising questions about the existence of evil, pain, and destruction.
The poem is divided into two parts, like many sonnets are. The first eight lines describe a “dimpled spider, fat and white,” perched on a type of flower known as the “heal-all, holding up a moth” with white wings. The whiteness of the spider echoes the whiteness of the moth, yet at the same time contrasts with the metaphorical darkness of its act (killing the moth). Ironically, the moth has been killed and will be eaten on a flower used in traditional medicine to heal a variety of ailments.
This irony is not lost on Frost, who notes that the three elements are “mixed ready to begin the morning right,” while also comparing them to the “ingredients of a witches’ broth.” On one hand, the spider has killed and will consume the moth simply because that is the nature of this lowly creature. This nature can’t be judged as unethical. On the other hand, Frost insists that readers see the act as essentially violent and dark: it is, in any case, a killing.
This perspective prepares readers for the final six lines of the sonnet. They explicitly ask what the healing flower had to do with the business of the spider and moth, and raise the question
What brought the kindred spider to that height,
Then steered the white moth thither in the night?
Why, in other words, did the moth have to die? What force compelled this? The laws of nature? A god? Frost registers shock that a “design of darkness to appall” would “govern a thing so small” as a spider killing a moth, consequently questioning the very essence of that design.