F. Scott Fitzgerald manages to define, praise, and condemn what is known as the American Dream in his most successful novel, The Great Gatsby. The novel is set in 1922, and it depicts the American Dream--and its demise--through the use of literary devices and symbols.
One literary device he uses to depict the American Dream is motif; one motif is geography as represented by East and West Egg. West Egg is where the "new rich" live, those who have made a lot of money by being entrepreneurial (or criminal) in the years after World War I ended. These people are portrayed as being rather gaudy (like Gatsby's pink suit and Rolls Royce), showy (like Gatsby's rather ostentatious white mansion), and gauche (socially awkward, as Gatsby seems always to be). It is as if they do not quite know what to do with their newly earned riches and therefore try to "copy" what they perceive to be the possessions and manners of the rich. This is a clear condemnation of the excessive materialism which was the result of pursuing the American Dream.
On the other hand, East Egg is filled with those who have always had money. While they do look like they have class, dignity, and manners (things lacking in West-Eggers), they are no better in their excesses than their newly rich neighbors. Tom and Daisy both have affairs, Jordan Baker is a cheat, Daisy kills a woman and lets someone else take the blame, and many of the East Eggers who come to Gatsby's parties bring their mistresses and act like heathens while they are there. The clear message seems to be that the result of the American Dream--wealth--causes destruction.
This is a highly symbolic novel, and Fitzgerald uses symbols to represent various aspects of the American Dream. The first is the Valley of Ashes, a place which depicts the consequences of the self-absorption of the rich. Nick says:
They were careless people, Tom and Daisy--they smashed up things and creatures and then retreated back into their money of their vast carelessness, or whatever it was that kept them together, and let other people clean up the mess they had made.
One of the results of this representative carelessness is the Valley of Ashes. The rich have made their money on industry and carelessly tossed the waste, resulting in this gray, poverty-stricken stretch of land. The people and the place matter not at all to those who selfishly left their waste for others to live in and deal with, another consequence of the American Dream, according to Fitzgerald.
An unmistakable symbol used to depict the American Dream, as well as its demise, is the green light at the end of Daisy's dock in East Egg. It is Gatsby's inspiration and his aspiration--the unattainable dream. When he was poor, Daisy could not marry him, so he worked hard and achieved the epitome of the American Dream. He literally recreated himself from virtually nothing, he made a lot of money (through illegal means, though no one seems to care much about that), and he surrounded himself with the material possessions which he thinks will entice Daisy to be with him. Nick philosophically compares the green light to the Pilgrims seeing America for the first time.
The dream soon dies, however.
[Gatsby] had come such a long way to this blue lawn, and his dream must have seemed so close he could hardly fail to grasp it. But what he did not know was that it was already behind him, somewhere in the vast obscurity beyond the city, where the dark fields of the republic rolled on under the night.