The quote from Richard Bachman's book "Thinner" describes an "asshole" as someone who disregards reality or refuses to accept the evidence before them. This suggests a lack of self-awareness and an inability to recognize the truth of a situation, which can lead to destructive behavior and strained relationships. This character flaw might stem from arrogance or a fear of confronting uncomfortable truths.

Moreover, the idea implies that such individuals often create challenges for themselves and others because of their refusal to acknowledge reality. Their behavior can be detrimental not only to themselves but also to those around them, as it breeds confusion and conflict. Accepting reality is critical for personal growth and maintaining healthy relationships.