How does The Great Gatsby reflect or challenge the argument from Steinbeck's essay "Paradox and Dream"? Provide quotes from The Great Gatsby for support.

"Paradox and Dream" is an essay by John Steinbeck in which he points out the contradictions in the beliefs and behaviors of Americans. He discusses politics, gender roles, belief systems, money, and self-reliance. The Great Gatsby is a novel about a man who exemplifies the American spirit of individuality, risk, and wealth as well as the ability to rise from a place of poverty to power.
Gatsby is a romantic who is sure he can recreate the past just as it was—who thinks he can control outcomes but who can't enjoy his own parties. He is a paradoxical character who is ruthlessly ambitious yet soft-hearted. He is tied to the past but careening toward to the future in a new age of jazz, liquor, fast cars, and possibly independent women.
Steinbeck's assessment of Americans as paradoxical—claiming self-reliance but losing the ability to do things for themselves each decade—is supported by the carefree but pointless lives of Jay Gatsby's friends in The Great Gatsby. Examples of how Gatsby contradicts himself also show up in his mysterious dealings, his facade of respectability that hides shady commerce, and his discomfort in portraying himself honestly. He seems to be pretending, but he does believe in a dream and in possibilities. He is making it up as he goes along, but he clings to a philosophy that sounds reasoned.
Gatsby often uses the phrase "old sport" to portray himself as someone from old money, while it is clear to Nick (the narrator) and the reader that he has gotten his wealth in recent years. In this way, he creates a pretense, but Nick can't tell what Gatsby's motivation is. Like Americans, Gatsby has it all but still wants more: he wants a reputation, a tradition, and a connection with the past.
Gatsby shows Nick a medal to prove he fought in the war, but Nick still finds it odd and wonders if it's true. As Gatsby hands the medallion to Nick, he says, "That's the one from Montenegro." The evidence of the metal still doesn't quite convince Nick.
Like the Americans Steinbeck dissects, Gatsby is future-oriented and believes he can make dreams come true. He watches a green light across the water (symbolizing love, money, or Daisy, depending on the interpretation) and Nick comments,

Gatsby believed in the green light, the orgiastic future that year by year recedes before us. It eluded us then.

Steinbeck is commenting on Americans in the 1940s, but not much has changed since the setting of The Great Gatsby in the 1920s. Americans still put on a show that they seem to deeply believe in, flout their practicality while running after money and status. There is a mythical quality in the American imagination, in being better than we actually are. Gatsby embodies this myth and suffers the consequences when the dream is overtaken by reality.