In "The Castle in the Forest," Norman Mailer presents a significant observation through the character's remark to Klara about the nature of stupidity. He suggests that a sign of foolishness is when a person becomes overly engrossed in their job to the point of thinking it holds more value than the roles of others. This idea implies that such arrogance can blind individuals to the broader perspectives and contributions of different people and professions.

The statement serves as a critique of narrow-mindedness and elitism that can arise from professional pride. Mailer emphasizes the importance of humility and the recognition that every occupation has its worth. By highlighting this dynamic, the narrative encourages readers to appreciate the diversity of roles in society, promoting a more egalitarian view of human endeavors.