The Good, The Bad, and The Gatsby.
The first symbol in "The Great Gatsby" is the symbol of the eyes of T.J. Eckleburg. This symbol was brought up early in the story, and is mentioned many times through out the rest of it. In the story it appers to be a billboard with the eyes of the oculist T.J. Eckleburg on it, surrounded by huge glasses. It sybolises the all seeing eyes of God, and how nothing can escape its gase.
The second symbol in the story is the green light at the end of the Buchanan's dock. This symbol is different from where you are in the story. At the begginging it stands for the hope that Gatsby will see Daisy again, and that she will want to be with him. At the end of the novel, it is almost like the light is mocking that hope.
The third symbol in the novel is The Valley Of Ashes. This is a place where the less wealthy live, and the industrial ash is dumped. It is true to its name, as the air is super dirty and ashy, and even Nick notices how off it feels. It symbolises how the rich will have their own pleasures, not caring for how it effects people they deem lesser then themselves.