A poem by Robert Burns, \"To a Mouse\" is about a farm worker who plows up a mouse and the hard work the mouse had done to create a home for itself. The line \"The best-laid plans of mice and men often go awry\" is the reference of the title. Both the novel and the poem deal with weaker creatures who are trapped in a world where they have little power and they can be wiped out with little or no regard. In the poem , the farm worker looks with sadness and compassion at the mouse and apologizes for destroying all its efforts. He then contemplates the reality of mortality. Steinbeck does the same with the ill-equipped George and Lennie.
In referring to the "general symbolism", I assume you are referring to what the story represents. You could also be asking about the symbolism of the title. I will present you with both answers.
The title refers to a poem by Robert Burns which includes these lines:
"the best laid plans o' mice and men/often do go wrong"
The book demonstrates this title through the characters of George and Lenny primarily. They have big plans of having their own place, being their own family and their own boss. Their plans seem possible when they meet Candy, who wants very much to join them. However, the disability of Lenny and the tragic events that cause him to mistakenly kill Curley's wife, put these plans to an end.
Overall, this book represents the isolation caused by the depression. The men and the one woman of this story have been isolated by a lack of choices and by poverty. They are all struggling to survive and have to abandon many dreams in order to do so. This causes them to become closed off, angry, and despondent. They turn on one another in their attempt to get ahead. The exceptions are George and Lenny, who have each other - until the end, when they two are isolated by their situation.
The book Of Mice and Men symbolises Steinbecks marxists views on the American Dream being used to control the mases and prevent a revolution in the great depression. It also refelects his feminist views with women being protrayed only as whores and mother figures, his opinions against racisim with crook's dream of racial inequality being somwhat unachievable and his ironic view that the happiest men (Curly and Carlson in the book) are those who have no dreams to be smashed! Quite funny really, considering this was the book that made him his millions!
(Im from england so i dont know how much of this may make sense over in america but looking at it from the angle of Steinbeck himself and what he is trying to say... it makes sense to me!!)
This book symbolizes the struggle of men during the great depresion.