"Sometimes a Great Notion" by Ken Kesey explores the complexities of family dynamics and individuality within a close-knit community. The phrase "A man is known by the mice he keeps" suggests that one’s character is often reflected in their associations and friendships. This idea emphasizes how personal relationships can shape perceptions and influence one's identity, as friends and companions can significantly impact a person's reputation and choices.

The novel delves into themes of loyalty, conflict, and the struggles of living in a society that often pressures individuals to conform. Kesey's characters navigate these challenges, revealing how their connections with others define them and shape their personal journeys. Through rich storytelling, the book invites readers to consider the importance of the relationships they cultivate and how these relationships, much like mice, can either uplift or hinder a man’s standing in the world.