The metaphorical title of John Steinbeck's novel is pivotal to the expression of power that wields its influence upon the lives of characters such as Candy, George, and Lennie. Like a mouse, George Milton is
"small and quick, dark of face, with restless eyes and sharp strong features. Every part of him was defined: small, strong hands, slender arms, a thin and bony nose."
The most complex of the characters in Of Mice and Men, George is exerts his intelligence, and he has ambitions. However, his "best laid plans go awry" because the forces of social power, represented by Curley, interfere. Curley, the boss's son, who intrudes into the fraternity of men in the bunkhouse with his soft gloved hand that he need not use exerts his influence. In an attempt to show his authority, he takes a swing at Lennie; however, Lennie, in deterring Curley from hitting him, has such force in his grip that he crushes Curley's hand. This act of Lennie's results in bitter hatred on Curley's part, so when Lennie gets into trouble, Curley has all the more reason to try to kill Lennie.
Another type of influential power that is exerted in Steinbeck's novella is spiritual. This power is represented by Slim, who with his "god-like eyes" sees much as George and he play cards; he also "hears more than what is being said." For instance, while he sympathizes with Candy, understanding his love for the old dog, Slim tells Candy that the dog has come to the end--much like old Candy himself. With his "calm eyes," Slim offers him one of his pups to take its place. And, since "Slim's opinions were law," Carlson, who is a mechanic with the coldness of steel in his heart, takes the old dog out and shoots it, an action that becomes of metaphor of Lennie's end.
The powers of materialism represented by Carlson the cold, brutal mechanic whose pistol overpowers the sensitive such as Candy and Lennie destroys George and Lennie's American dream of having a place of their own. There is little that the spiritual power found in Slim can do other than offer sympathy to George whose well-laid plans go awry. He says, "You hadda, George. I swear you hadda" while the mechanical, insensitive Carlson asks, "Now what the hell you suppose is eating them two guys?"