The Wasp Factory is deeply interested in its characters’ mental states, especially in how those mental states relate to their behavior. Importantly, the novel is not interested in mental disorders writ large, but rather in the particular subset that manifest in violent and obsessive actions and a callous personality. In particular, the novel engages with questions of evil, especially in relation to childhood, and the nature/nurture-origin debate of psychopathy. Psychopathy is a mental disorder typically identified by a person’s lack of empathy, deficient affect, and inability to regulate behavior. This state makes an act like murder easier for someone like Frank who has no consideration for the suffering his actions might cause victims or their families. Given Frank’s young age and the typical attribution of innocence to childhood, The Wasp Factory challenges expectations and essentially asks, “Can children be evil?”

Through Frank’s narration of his and Eric’s lives growing up, another question develops: “If children can be evil, is that something innate or developed?” Both Frank’s and Eric’s behaviors seemingly have an origin story, suggesting that their psychopathy was nurtured, but Frank’s unreliable narration and the extremity of both brothers’ actions indicate that nature cannot be discounted. 

Angus’s treatment of his sons—particularly Frank—makes it difficult to imagine a scenario where they escaped his influence and retained desirable mental health.