The title of the book comes from a poem by the 18th century Scottish poet Robert Burns. It is about a mouse which carefully builds a winter nest in a wheat field, only for it to be destroyed by a ploughman. It is written in Scots dialect.
The best laid schemes o' mice an' men
Gang aft a-gley,
An' lea'e us nought but grief an' pain,
For promised joy!
(The best laid schemes of mice and men
Often go wrong
And leave us nothing but grief and pain,
Instead of promised joy!)