Bring on the tough stuff - there’s not just one right answer.
Of Mice and Men feels like an allegory, with each character possessing a specific trait that represents something or some group in society. So, is the book just a heavy-handed lecture about how nasty people are to each other. Are all of these wrongs (racism, sexism, discrimination) treated as equally evil? Or are the characters real, individual people, rather than being merely types/symbols?
The setting here is very specific. Do the events of the story only apply to this particular place and time, or can the novel be thought of as universally applying to humans everywhere?
Why does George have to give up the idea of the dream farm once Lennie kills Curley's wife? Was the farm ever a real possibility?
How are the deaths of Candy's dog and Lennie related? Why do the two have to die? Is it fair to draw a comparison between these two events? Are Candy's dog's death and Lennie's death just different degrees of the same kind of thing?
Does any character escape prejudice? Is any character not prejudiced? Given everyone's interaction with each other, how does prejudice actually operate in the novel? Is prejudice just a code word covering for some larger human failing and tendency towards suspicion and isolation?
Does George have the right to kill Lennie? Legally? What about ethically? How does Steinbeck's treatment of Lennie's murder affect the way the reader interprets the event? What does George's action suggest about justice—within the play and in the world as a whole?
The natural world is often described as beautiful and peaceful in the book, though it's tempered with all sorts of awful occurrences. What role does the natural world actually play in the novel?
How are the notions of power and shifts in power important here? Who has power and why? Are there different types of power?
What is Steinbeck saying about dreams? Is the book's take-home message inherently pessimistic one? Should we all just give up and stop dreaming?