The central themes of The Great Gatsby, to me, have to do with identity. How do we become the real version of ourselves? Are we born or shaped into our final identities?
I don't know that there is a definitive answer to this question provided in the novel, but Gatsby's example seems to suggest that there is something in each of us that is present when we are young and stays with us through our lives.
Perhaps the Great Gatsby is both a satire of the "nouveau riche" and as well as an almost poetic complaint of Fitzgerald's own life similar to T.S. Eliot's lines,
In this sense it is tragic portrayal of hollow lives that have been wasted upon false values.We are the hollow men We are the stuffed men Leaning together Headpiece filled with straw. Alas! Our dried voices, when We whisper together Are quiet and meaningless
Ms-charleston-yawp beat me to my point. While this novel is not exactly or completely biographical, Fitzgerald is awfully close to Jay Gatsby. He didn't get the girl because he was too poor; he had to work hard to make it big enough to get her; he finally got her but their life together was a roller coaster ride of highs and lows; he died too young, an unhappy and unsatisfied man. Sound familiar? His disillusionment with having money, with a society which valued money over people, and with a world which seemed concerned only with consoling itself for its war wounds by excessiveness in all things was reflected in this work, as well. This novel is a picture of Fitzgerald's life.
Just to take a little bit different view on this awesome question, I focused on the "primary motivation" aspect for Fitzgerald himself. That part of it is pretty easy. F. Scott Fitzgerald desired to become famous in the literary world for one reason: to obtain Zelda Sayre. In fact, it is incredibly ironic that this reason directly mirrors the one desire of Gatsby: to obtain Daisy Buchanan. Once Fitzgerald obtained Zelda (and furthermore became his wife), he desired to continue in that famous vein in order to keep her favor.
I suppose another minor motivation was to keep up his lavish, spendthrift, and indulgent lifestyle. Fitzgerald was pretty famous for both throwing and attending lavish parties, again, (the former being) very similar to Gatsby.
Finally, I believe (and this is literally my own opinion) there is an underlying motivation that Fitzgerald is calling out for help psychologically. Gatsby has an incredibly skewed personality. Fitzgerald is the living equivalent to Gatsby. Both were destined for a short and fairly devastating life. I have always found it strange that absolutely NO ONE in Fitzgerald's life called attention to this. But again, this is simply my own opinion.
I think that you can find many particular claims in Fitzgerald’s work. One dominant claim is to raise a sense of understanding about the sadness and fragility of the Jazz Age. I cannot find a better metaphor about the study of the 1920s than what Fitzgerald depicted in the lives of characters in West and East Egg. The fundamental claim that seems to be made is that the image of wealth, happiness, and social acceptance was a veneer, a cover, that masked the pain and hollowness that eventually ripped through the illusion in a stunningly brutal way leading into the Great Depression. When we see Gatsby’s futile pursuits at Daisy and, in a sense, happiness, the reader fully grasps the extent to which the 1920s was a beautiful monument built upon a firmament of sand with the tide waiting to crash in quite a dramatic fashion. The denouncing of superficiality in both emotional relationships and social expectations comes out as a dominant claim in Fitzgerald’s work.
F. Scott Fitzgerald was considered the spokesman for the Jazz Age, which was a time of excess.
The reaction to the horrors of WW I seemed to be an over reaction. The 20s roared. Society changed. We went from a Victorian mindset to an eat drink and be merry attitude. The waltz gave way to the Charleston. Women's fashion went from austerity to the flapper. All this and more is reflected in The Great Gatsby.
He shows us a self made man, Gatsby, who desperately wants to fit into with the uber rich. Gatsby has idealized Daisy as the 20s idealized their false perspective of the world. There was a superficiality in the world of both East and West Egg. Relationships were superficial.
In the end, Nick chooses to return to his Midwestern roots, realizing what really matters and that the worlds of both the Buchanans and Gatsby are doomed to fall
You should read the "themes" section of the analysis of this novel here on eNotes (see the link below). This will give you an idea of what Fitzgerald was trying to accomplish in this novel. It was written in the 1920s and shows how disillusioned people were after the end of World War I, the Great War, the "war to end all wars." So many people were killed in this first modern war, and much of Europe was destroyed. Many writers of this time period were disillusioned, even American writers like Fitzgerald. In this novel, Fitzgerald showed the negative results of blind ambition -- despair, and disillusionment. Behind the glitz and glamour of the upper class, was a hollow emptiness in the souls of people that nothing could fulfill, even if one DID achieve the so-called American dream. Gatsby is an example of this. He is "nouveau riche" - newly rich, but he does not have class. He believes he can win the girl if he has enough money, but this proves not to be true. In spite of the trappings of wealth, he does not have family money, and cannot ever hope to compete in Daisy's world.
Read more about the other themes - class, the nature of reality, and the clash of cultures at the link below - I will not repeat what is already there.
Scott Fitzgerald's "The Great Gatsby" is a satire which exposes the hollowness and meaninglessness of the word "Great." Scott Fitzgerald's main in writing the novel is to expose the sham life and the illusions of Jay Gatsby. He does it in the following five ways:
1. Family background: In Ch.4 Gatsby tells Nick, "I'll tell you God's truth...I am the son of some wealthy people in the middle-west [San Francisco]." The facts about Gatsby's [James Gatz'] past are revealed in Ch.6 and Gatsby himself reveals the truth about his past to Nick:"He told me all this very much later".
2. His wealth: In Ch.2 Mr. McKee remarks that he had attended one of Gatsby's parties and adds: "Well they say he's a nephew or a cousin of Kaiser Wilhelm's (the German Emperor). That's where all his money comes from." In Ch.6 Gatsby reveals to Nick that "it was from Cody that he inherited money-a legacy of twenty-five thousand dollars."
3. Oxford education: In Ch.4 Gatsby tells Nick that he was educated at Oxford. In Ch.7 Gatsby reveals the truth to Tom that he stayed only five months there and "that's why I can't really call myself an Oxford man."
4. Proximity to Daisy: In Ch.4 Jordan Baker tells Nick that "Gatsby bought that house so that Daisy would be just across the bay." In Ch.5 after Gatsby had shown Daisy around his house and after Daisy had put her arm though his he realises the vast distance actually separating him and Daisy: "It had seemed as close as a star to the moon."
5.Daisy's love for Gatsby: At the end of Ch7 the reality is that and Tom and Daisy are reconciled and the illusion that Daisy loved Gatsby is shattered.