The paradox in the story lies in the detective's admission that "If there’s one thing I know, it’s that I know nothing." This statement highlights a contrast between the certainty expressed by the townspeople and the detective's humility and acknowledgment of her own limitations. While the citizens are confident in their theories and beliefs about the brown lawns, the detective embodies a more skeptical and analytical approach that recognizes the complexity of the situation.
This paradox serves to emphasize the theme of knowledge versus ignorance. The townspeople, despite their confidence, are ultimately misguided in their assumptions about the cause of the problem. In contrast, the detective, who claims to know nothing, is the one who uncovers the truth, which is a result of an underground pipe break, something nobody anticipated.
The function of the paradox in the story illustrates that knowledge is not merely about the accumulation of facts or theories, but also about understanding the limits of one's understanding. It suggests that sometimes, admitting ignorance can lead to deeper insight, while blind confidence can result in misunderstanding the situation at hand. This ultimately drives home the idea that true wisdom may lie in questioning assumptions and being open to unexpected revelations.