In Of Mice and Men, Steinbeck holds on to the idea of the desire to belong. From the beginning of the novel, Lennie and George hold on to each other even though they are drastically different because they want to belong. Lennie often comments that they always have each other no matter what happens. The desire to belong is prominent in the scene between Lennie and Curley's wife. She reveals to Lennie that she just wants company because Curley treats her poorly. She feels totally out of place on the farm because she is the only woman and the men see her as being "fast." Lennie also wants people to like him and to feel like he fits in with the other men. So the idea of the desire to belong is traced throughout the course of the novel.
Much like Steinbeck’s short novel The Pearl, Of Mice and Men is a parable that tries to explain what it means to be human. Essentially, man is a very small part of a very large universe; in the greater scheme of things, individuals come and go and leave very little, lasting mark. Yet deep inside all people is a longing for a place in nature—the desire for the land, roots, and a place to call “home.” The struggle for such a place is universal, and its success is uncertain.
In sharing his vision of what it means to be human, Steinbeck touches on several themes: the nature of dreams, the nature of loneliness, man’s propensity for cruelty, powerlessness and economic injustices, and the uncertainty of the future.