A Socialist and a Realistic writer, Steinbeck chose to deviate from the norm by writing not about the middle class, but instead about the poorer class who suffered terribly during the Great Depression. His novella Of Mice and Men chronicles the confusion and hopelessness of the lower class that found themselves dispossessed and alone in their struggles.
The old swamper, Candy, and his dog find themselves in this position of hopelessness and confusion, a theme of Of Mice and Men. With his one hand gone from a farming accident, Candy finds himself relegated to merely cleaning up the bunkhouse on the ranch. Consequently, he worries that he will outlast his usefulness and be "sloughed." When Carlson, the mechanic, enters the bunkhouse, complaining of the smell of the old dog, Candy becomes fearful as Carlson offers to put the dog out of its misery. Not only does Candy not wish to lose his old friend--his only companion--but he becomes anxious that a similar opinion has been formed about his own usefulness.
After the tragic end of his beloved pet, he relief that Candy feels when he is allowed to be part of George and Lennie's plan to own a place that will be theirs is, indeed, understandable. For, it is in the fraternity of man that the individual finds solace from the confusion of his isolation and hopelessness. Joined with George and Lennie, Candy has, as Crooks has observed, someone by whom he can "measure" himself; joined with others, Candy no longer feels hopeless as he envisions a future. Unfortunately, however, when Lennie accidentally kills Curley's wife, Candy again senses his terrible plight: He is again alone and faces the fate of his doomed dog.