The title of Steinbeck’s novel comes from the poem ‘To a Mouse’, by the Scottish poet Robert Burns (1759–96). It is addressed to a mouse that builds its winter nest in a wheat field, only to see it destroyed by a ploughman. Burns wrote his poem in Scots dialect.

The best laid schemes o’ mice an’ men
The best planned schemes of mice and men
Gang aft a-gley,
Often go wrong,
An’ lea’e us nought but grief an’ pain,
And leave us nothing but grief and pain
For promis’d joy!
Instead of the joy they promised!

This is relevant to Steinbeck’s novel in two ways:

  1. Steinbeck’s characters seem to be at the mercy of fate, almost as powerless as mice.
  2. A major theme of the novel is ‘shattered dreams’. Lennie and George are migrant farm workers who dream of having their own home and land, but this dream is wrecked, like the mouse’s nest in the poem.
In addition, it calls up the proverbial phrase: ‘Are you a man or are you a mouse?’ At the core of the novel is a test of manhood. George has to man up to a tough choice: shoot Lennie and put him out of his misery, admit defeat – or do nothing and leave him to the hands of Curley, the rage of the mob or the madhouse.
This theme is brought out where Candy says near the end of Chapter Three: “I ought to of shot that dog myself, George. I shouldn’t ought to of let no stranger shoot my dog.”

Further, the killing begins with mice. George says “the trouble with mice is you always kill ’em”. Later, Lennie kills the pup, which Curley’s wife says is “only a mutt”. Then he kills her. Lennie’s killing moves inevitably from mice to men, from small to large.