The best examples of naturalism in John Steinbeck's Of Mice and Men are to be found in his characterizations. Steinbeck knew that human beings are not all good or all bad, as they are, for example, in many of the works of Charles Dickens. Steinbeck's characters in his short novel are mostly mixtures of both good and bad qualities. Three examples of naturalism in his depiction of characters are easily found in George Milton, Curley's wife, and Crooks.
George shows his good side in his caring for Lennie, in accordance with his promise to Aunt Clara as well as in his simple good-heartedness. However, he frequently gets angry at Lennie and abuses him verbally, as he does in the first chapter.
"God a'mighty, if I was alone I could live so easy. I could go get a job an' work, an' no trouble. No mess at all, and when the end of the month come I could take my fifty bucks and go into town and get whatever I want....An' whatta I got," George went on furiously. "I got you! You can't keep a job and you lose me ever' job I get."
There is much more of this, ending with:
"I wisht I could put you in a cage with about a million mice an' let you have fun."
Curley's wife is presented as a pretty and lonely young girl who is flirtatious but relatively harmless. Yet in the fourth chapter she becomes vicious with Crooks.
She turned on him in scorn. "Listen, nigger," she said. "You know what I can do to you if you open your trap?"
She closed in on him. "You know what I could do?"
Crooks seems to grow smaller, and he pressed himself against the wall. "Yes, ma'am."
"Well, you keep your place then, nigger. I could get you strung up on a tree so easy it ain't even funny."
What she means, of course, is that she could accuse him of attempted rape.
Crooks himself seems like an especially pitiful figure because he is even more lonely than the other workmen, who will pitch horseshoes with him but won't let him sleep in the same bunkhouse because of their racial prejudice. Yet Crooks has a bad side to his character, and he displays this in his psychological cruelty to poor, dumb Lennie in the same chapter.
"S'pose George don't come back no more. S'pose he took a powder and just ain't coming back. What'll you do then?"
Lennie's attention came gradually to what had been said. "What?" he demanded.
"I said s'pose George went into town tonight and you never heard of him no more."
"He don't do it," Lennie cried. "George wouldn't do nothing like that....Don't you think he will?"
Crooks' face lighted with pleasure in his torture.
We can understand why Crooks should want to torture Lennie. It is mainly because Lennie is the only person he could tortune. He has to keep a very low profile as the only black man on the ranch. Crooks leads a life of mental and physical pain. He is especially lonely because the other workers make no effort to hide their bigotry. He tries to pretend he doesn't care and that he prefers his privacy and solitude; but he feels continuously humiliated by being forced to live alone in the smelly tackle room off the barn with only the horses for companions. And he suffers physically from his ruined body. The chapter ends when the others leave him alone and:
Crooks sat on his bunk and looked at the door for a moment, and then he reached for the liniment bottle.
Crooks takes his mental and physical suffering out on Lennie, because it seems to be a rule of human nature that a person who is abused will react by abusing someone else.