Of Mice and Men teaches a grim lesson about the nature of human existence. Nearly all of the characters, including George, Lennie, Candy, Crooks, and Curley's wife, admit, at one time or another, to having a profound sense of loneliness and isolation
From bad, through competent and good to great, and the classification is seemingly well-defined and mostly outside our control. I read this in my English book about a week ago. Hope this answer helps and mark as.
