Wilde uses a foil in “The Happy Prince” to emphasize the opposing characteristics of the rich and poor. The seamstress, for example, serves as a foil for the Queen’s "maids-of-honour," for whom she is making a luxurious dress:
Her face is thin and worn, and she has coarse, red hands, all pricked by the needle, for she is a seamstress. She is embroidering passion-flowers on a satin gown for the loveliest of the Queen’s maids-of-honour to wear at the next Court-ball. In a bed in the corner of the room her little boy is lying ill. […] His mother has nothing to give him but river water, so he is crying.
Wilde emphasizes the seamstress’s diligence, with her face made “thin and worn” and her hands turned “coarse” and “red” by her work. The poverty of her situation (with her son sick and helpless) strongly contrasts the luxury of the decorative “satin gown” she is making. The seamstress’s industriousness is further highlighted when the Swallow sees the maid-of-honour—for whom the dress is being made—when she emerges onto a balcony at one of the palace dances:
“I hope my dress will be ready in time for the State-ball,” she answered; “I have ordered passion-flowers to be embroidered on it: but the seamstresses are so lazy.”
The maid-of-honour’s branding of the seamstresses as lazy reveals her ignorance to the industriousness of the town’s workers. The irony of her comment is emphasized by its context, with the maid-of-honour speaking to a lover at a palace dance and, in this way, reveling in luxury while supposedly "lazy" people like the seamstress work so hard that they barely have time to care for their own children. Such situational irony emphasizes the broader contrast between the idleness of the town’s rich and the industriousness of its poor.
As is typical of Wilde’s style of writing, “The Happy Prince” is steeped in irony, with the story repeatedly flipping readers’ expectations. This irony is introduced immediately through the Happy Prince himself, who, despite his name and the townspeople's perception of him, is miserable. Although a mother scolds her son for crying by saying “the Happy Prince never dreams of crying for anything,” when the Swallow meets the Happy Prince there are “tears […] running down his golden cheeks.”
The Happy Prince’s explanation of his name speaks to just how superficial and misleading outward appearances can be:
“My courtiers called me the Happy Prince, and happy indeed I was, if pleasure be happiness. So I lived and so I died. And now that I am dead they have set me up here so high that I can see all the ugliness and all the misery of my city, and though my heart is made of lead yet I cannot choose but weep.”
The Happy Prince’s happiness is exposed as a surface-deep “pleasure,” and he suggests that the only way he could be truly happy would be if he were capable of overlooking all of the misery surrounding him. The reality of the Happy Prince’s sorrow—which contradicts his name—creates an obvious clash that alerts the reader to the deceptiveness of appearance in this story, with Wilde’s choice of “The Happy Prince” as the title confirming the significance of this theme.
Wilde exposes the deceptiveness of appearances further by showing the characters’ poor judgment of value in the story. The statue of the Happy Prince, for example, is valued least when it has done the most good. While the statue of the Happy Prince is revered and admired by the townspeople at the beginning of the story (when it's covered in gold and jewels), it is later disparaged as “shabby” and pulled down after it has been stripped of its outer shiny layer.
“As he is no longer beautiful, he is no longer useful,” said the art professor.
This statement is highly ironic because, as the reader has just seen in the story, the loss of the statue’s beauty is directly related to the Happy Prince’s attempt to help the town’s poor. The ending of the story makes this poor value judgment clear, with God proclaiming the statue’s leaden heart—which has been thrown away by the townspeople—as one of the two “most precious things in the city.” That the Prince is able to feel the most empathy and compassion when his heart is made of lead further emphasizes the deceptiveness of appearance and exposes the superficiality that permeates the town. Just as the statue of the Happy Prince is only gilded in gold, appearances are shown to run surface deep.